COVID-19 lab leak theory

This article is about the hypothesis proposing SARS-CoV-2 came from a laboratory. For bioweapon conspiracy theories, see COVID-19 misinformation § Bio-weapon.

The COVID-19 lab leak theory, or lab leak hypothesis, is the idea that SARS-CoV-2, the virus that caused the COVID-19 pandemic, came from a laboratory. This claim is highly controversial; most scientists believe the virus spilled into human populations through natural zoonosis (transfer directly from an infected non-human animal), similar to the SARS-CoV-1 and MERS-CoV outbreaks, and consistent with other pandemics in human history.^[1] Available evidence suggests that the SARS-CoV-2 virus was originally harbored by bats, and spread to humans from infected wild animals, functioning as an intermediate host, at the Huanan Seafood Market in Wuhan, Hubei, China, in December 2019.^[5][6] Several candidate animal species have been identified as potential intermediate hosts.^[13] There is no evidence SARS-CoV-2 existed in any laboratory prior to the pandemic,^[14][15][16] or that any suspicious biosecurity incidents happened in any laboratory.^[17]

The Wuhan Institute of Virology in Wuhan, China

Many scenarios proposed for a lab leak are characteristic of conspiracy theories.^[18] Central to many is a misplaced suspicion about the proximity of the outbreak to a virology institute that studies coronaviruses, the Wuhan Institute of Virology (WIV). Most large Chinese cities have laboratories that study coronaviruses,^[14][19] and virus outbreaks typically begin in rural areas, but are first noticed in large cities.^[20] If a coronavirus outbreak occurs in China, there is a high likelihood it will occur near a large city, and therefore near a laboratory studying coronaviruses.^[20][21] The idea of a leak at the WIV also gained support due to secrecy during the Chinese government's response.^[14][22] The lab leak theory has been described as racist and xenophobic; belief in the lab leak theory is correlated with distrust of government and anti-China sentiment, and has kindled the latter.^{[citation needed]} Scientists from WIV had previously collected SARS-related coronaviruses from bats in the wild, and allegations that they also performed undisclosed risky work on such viruses are central to some versions of the idea.^[23][24] Some versions, particularly those alleging genome engineering, are based on misinformation or misrepresentations of scientific evidence.^[25][26][27]

The idea that the virus was released from a laboratory (accidentally or deliberately) appeared early in the pandemic.^[28][29] It gained popularity in the United States through promotion by conservative personalities in early 2020,^[30] fomenting tensions between the U.S. and China.^[31] Scientists and media outlets widely dismissed it as a conspiracy theory.^[32][33] The accidental leak idea had a resurgence in 2021.^[34] In March, the World Health Organization (WHO) published a report which deemed the possibility "extremely unlikely", though the WHO's director-general said the report's conclusions were not definitive.^[35] Subsequent plans for laboratory audits were rejected by China.^[22][36]

Most scientists remain skeptical of the possibility of a laboratory origin, citing a lack of any supporting evidence for a lab leak and the abundant evidence supporting zoonosis.^[15][37] Though some scientists agree a lab leak should be examined as part of ongoing investigations,^[38][39] politicization remains a concern.^[40][41] In July 2022, two papers published in Science described novel epidemiological and genetic evidence that suggested the pandemic likely began at the Huanan Seafood Wholesale Market and did not come from a laboratory.^[16][42][5]

Background

Main article: Severe acute respiratory syndrome coronavirus 2 § Reservoir and origin

The principal hypothesis for the origin of SARS-CoV-2 is that it become infectious to humans through a natural spillover event (zoonosis). That it became infectious to humans through escape from a laboratory where it was being studied is a minority position. The available evidence supports zoonosis.^[43][18] Although the origin of SARS-CoV-2 is not definitively known, arguments used in support of a laboratory leak are characteristic of conspiratorial thinking.^[18]

Zoonosis

Most new infectious diseases begin with a spillover event from animals,^[40] and furthermore, they spillover spontaneously (either by contact with wildlife animals, which are the majority of cases, or with farmed animals).^[44][45] For example, the emergence of Nipah virus in Perak, Malaysia, and the 2002 outbreak of SARS-CoV-1 in Guangdong province, China, were natural zoonosis traced back to wildlife origin.^[44] COVID-19 is considered by scientists to be "of probable animal origin".^[45] It has been classified as a zoonotic disease (naturally transmissible from animals to humans). Some scientists dispute this classification, since a natural reservoir has not been confirmed.^[46][45] The original source of viral transmission to humans remains unclear, as does whether the virus became pathogenic (capable of causing disease) before or after a spillover event.^[47][48][49]

Bats, a large reservoir of betacoronaviruses, are considered the most likely natural reservoir of SARS‑CoV‑2.^[50][51] Differences between bat coronaviruses and SARS‑CoV‑2 suggest that humans may have been infected via an intermediate host.^[52][13] Research into the natural reservoir of the virus that caused the 2002 SARS outbreak has resulted in the discovery of many SARS-like coronaviruses circulating in bats, most found in horseshoe bats. Analysis indicates that a virus collected from Rhinolophus affinis in a cave near the town of Tongguan in Yunnan province, designated RaTG13, has a 96% resemblance to SARS‑CoV‑2.^[53][54][55] The RaTG13 virus genome was the closest known sequence to SARS-CoV-2 until the discovery of BANAL-52 in horseshoe bats in Laos,^[56][50][57] but it is not its direct ancestor.^[26] Other closely related sequences were also identified in samples from local bat populations in Yunnan province.^[58] One such virus, RpYN06, shares 97% identity with SARS-CoV-2 in one large part of its genome, but 94% identity overall. Such "chunks" of very highly identical nucleic acids are often implicated as evidence of a common ancestor.^[59][60]

An ancestor of SARS-CoV-2 likely acquired "generalist" binding to several different species through adaptive evolution in bats and an intermediate host species.^{[13][61][62][63]} Estimates based on genomic sequences and contact tracing have placed the origin point of SARS-CoV-2 in humans as between mid-October and mid-November 2019.^[64][65] Some scientists (such as Fauci above and CIRAD's Roger Frutos) have suggested slow, undetected circulation in a smaller number of humans before a threshold event (such as replication in a larger number of hosts in a larger city like Wuhan) could explain an undetected adaption period.^[32]

The first known human infections from SARS‑CoV‑2 were discovered in Wuhan, China, in December 2019.^[53] Because many of the early infectees were workers at the Huanan Seafood Market,^[66][67] it was originally suggested that the virus might have originated from wild animals sold in the market, including civet cats, raccoon dogs, bats, or pangolins.^[49][52] Subsequent environmental analyses demonstrated the presence of SARS-CoV-2 in the market, with highest prevalence in areas of the market where animals known to be susceptible to SARS-CoV-2 infection were held.^[4][6] Early human cases clustered around the market, and included infections from two separate SARS-CoV-2 lineages.^[4][6] These two lineages demonstrated that the virus was actively infecting a population of animals in the market, and that sustained contact between those animals and humans had allowed for multiple viral transmissions into humans.^[4][6] All early cases of COVID-19 were later shown to be localized to the market and its immediate vicinity.^[6]

While other wild animals susceptible to SARS-CoV-2 infection are known to have been sold at Huanan, no bats or pangolins were sold at the market.^[68][6]

Wuhan Institute of Virology

The Wuhan Institute of Virology and the Wuhan Center for Disease Control are located within miles of the original focal point of the pandemic, Wuhan's Huanan Seafood Wholesale Market, and this very closeness has made it easy for conspiracy theories to take root suggesting the laboratory must be the virus' origin.^[18] However virology labs are often built near potential outbreak areas.^[21] Proponents of the lab leak theory typically omit to mention that most large Chinese cities have coronavirus research laboratories.^[19] Virus outbreaks tend to begin in rural areas, but are first noticed in large cities.^[20] Stephan Lewandowsky and colleagues write than in itself, the location of the Institute is "literally a coincidence" and using it as a priori evidence for a lab leak typifies the kind of conjunction fallacy.^[18]

 

Phylogenetic tree of SARS-CoV-2 and closely related betacoronaviruses (left) and their geographic context (right)

The Wuhan Institute of Virology (WIV) had been conducting research on SARS-like bat coronaviruses since 2005,^[69] and was involved in 2015 experiments that some experts (such as Richard Ebright) have characterized as gain-of-function.^[24][70] Others (including Ralph Baric) have disputed the characterization, pointing out that the experiments in question (involving chimeric viruses) were not conducted at the WIV, but at UNC Chapel Hill, whose institutional biosafety committee assessed the experiments as not "gain-of-function".^[71] Baric did acknowledge the risks involved in such studies, writing, "Scientific review panels may deem similar studies building chimeric viruses based on circulating strains too risky to pursue ... The potential to prepare for and mitigate future outbreaks must be weighed against the risk of creating more dangerous pathogens."^[24][72]

The fact that the lab is in Wuhan, the city where the pandemic's early outbreak took place,^[73] and the fact that the research at WIV was being conducted under the less stringent biosafety levels (BSL) 2 and 3,^[24][74] has led to speculation that SARS-CoV-2 could have escaped from the Wuhan lab.^[23] Richard Ebright said one reason that lower-containment BSL-2 laboratories are sometimes used is the cost and inconvenience of high-containment facilities.^[24][75] Australian virologist Danielle Anderson, who was the last foreign scientist to visit the WIV before the pandemic, said the lab "worked in the same way as any other high-containment lab". She also said it had "strict safety protocols".^[76] The Huanan Seafood Market may have only served as a jumping off point for a virus that was already circulating in Wuhan, facilitating rapid expansion of the outbreak.^[47][77]

Prior lab leak incidents and conspiracy theories

Laboratory leak incidents have occurred in the past.^[78][79] A Soviet research facility in 1979 leaked anthrax and at least 68 people died.^[80] The 2007 foot-and-mouth outbreak in the UK was caused by a leaky pipe at a high-security laboratory.^[80] The SARS virus escaped at least once, and probably twice, from a high-level biocontainment laboratory in China.^[81][15][82]

Benign exposures to pathogens (which do not result in an infection) are probably under-reported, given the negative consequences of such events on the reputation of a host institution and low risk for widespread epidemics.^[83] Epidemiologist Marc Lipsitch and bacteriologist Richard Ebright have said that the risk of laboratory-acquired infection (especially with modified pathogens) is greater than widely believed.^[84][85]

No epidemic has ever been caused by the leak of a novel virus.^[14] The only incident of a lab-acquired infection leading to an epidemic is the 1977 Russian flu which was probably caused by a leaked strain of H1N1 that had circulated naturally until the 1950s.^[14]

Previous novel disease outbreaks, such as AIDS, H1N1/09, SARS, and Ebola have been the subject of conspiracy theories and allegations that the causative agent was created in or escaped from a laboratory.^[86][87][15] Each of these is now understood to have a natural origin.^[27]

Proposed scenarios

See also: Investigations into the origin of COVID-19

The lab leak theory is not a single discrete proposed scenario, but a collection of various proposed scenarios on a spectrum with, at one end, a careless accident from legitimate research; at the other, the engineering and release of a Chinese biological weapon.^[18] While the proposed scenarios are theoretically subject to evidence-based investigation, it is not clear than any can be sufficiently falsified to placate lab leak supporters, and they are fed by pseudoscientific and conspiratorial thinking.^[18]

There is no evidence that any laboratory had samples of SARS-CoV-2, or a plausible ancestor virus, prior to the start of the COVID-19 pandemic.^[14]

Various sources have hypothesised that SARS-CoV-2 could have leaked from the Wuhan Institute of Virology or another laboratory in Wuhan, such as the Wuhan Center for Disease Control. The theories vary on whether this was an intentional act or an accident. Theories also vary on whether the virus was modified by human activity prior to being released. By January 2020 some lab leak proponents were promoting a narrative with conspiracist components; such narratives were often supported using "racist tropes that suggest that epidemiological, genetic, or other scientific data had been purposefully withheld or altered to obscure the origin of the virus."^[19] David Gorski refers to "the blatant anti-Chinese racism and xenophobia behind lab leak, whose proponents often ascribe a nefarious coverup to the Chinese government".^[88] The use of xenophobic rhetoric also caused a rise in anti-Chinese sentiment.^[89]

On social media the idea that COVID was a Chinese biological weapon has become widespread, and accords with rhetoric about how a yellow peril threatens white people.^[90] Science historian Fred Cooper and colleagues write that in the United Kingdom, attitudes to the Chinese have long been tainted by xenophobic stereotypes. Cooper draws a parallel between the Wuhan lab leak narrative, and the machinations of fictional supervillain Fu Manchu, who is "expert in the deadly application of animal and biological agents" and who has been depicted on television shows as threatening the West with lethal diseases.^[91]

Origins

In the early days of the COVID-19 pandemic, speculation about a laboratory leak was confined to conspiracy-minded portions of the internet, including 4Chan and Infowars, but the ideas began to get wider traction after accusations about a "Chinese bioweapon" were originally published by Great Game India and then republished by the Red State Watch and Zero Hedge web sites.^[92] From there, the idea gained media traction and was championed by American conservative political figures.^[92]

The idea split into variants, including one that proposed Asian people were immune to COVID, or that the Chinese had a secret vaccine standing by for use. Some proposed that the Chinese government and World Health Organization were operating together in a conspiracy.^[92] The American president of the time, Donald Trump, used anti-Chinese rhetoric (such as "Kung flu") to feed the idea, and said in an April 2020 news conference that he had documents supporting the idea that SARS-CoV-2 had come from the Wuhan Institute of virology.^[92]

In reaction to this politicized environment, most mainstream science and media sources assumed that the lab leak idea was no more than racially-fuelled propaganda, and by the summer of 2020 the idea was largely dismissed, until the next American president, Joe Biden, ordered an investigation into COVID's origins in 2021.^[92]

Accidental release of a natural virus

Some have hypothesised the virus arose in humans from an accidental infection of laboratory workers by contact with a sample extracted from a wild animal or by direct contact with a captive animal or its respiratory droplets or feces.^[32]

Former CDC director Robert R. Redfield said in March 2021 that in his opinion the most likely cause of the virus was a laboratory escape, which "doesn't imply any intentionality", and that as a virologist, he did not believe it made "biological sense" for the virus to be so "efficient in human to human transmission" from the early outbreak. The fact that scientists have not been successful in finding an intermediate host that picked up the virus from bats and passed it to humans is seen by some as evidence that supports a lab leak, according to The Guardian.^[93][94]

University of Utah virologist Stephen Goldstein has criticized the scientific basis of Redfield's comments, saying that since SARS-CoV-2's spike protein is very effective at jumping between hosts, one shouldn't be surprised that it transmits efficiently among humans. Goldstein noted "If a human virus [such as SARS-CoV2] can transmit among mink, there's no basis to assume a bat virus [also SARS-CoV2] can't transmit among humans. Us humans may think we're very special – but to a virus we are just another mammalian host."^[95]

WHO assessment

The WHO-convened Global Study of Origins of SARS-CoV-2, written by a joint team of Chinese and international scientists and published in March 2021,^[38][96] assessed introduction through a laboratory incident to be "extremely unlikely" and not supported by any available evidence,^[50][97] although the report stated that this possibility could not be wholly ruled out without further evidence.^[32] The report stated that human spillover via an intermediate animal host was the most likely explanation, with direct spillover from bats next most likely. Introduction through the food supply chain and the Huanan Seafood Market was considered less likely.^[50]

A small group of researchers said that they would not trust the report's conclusions because it was overseen by the Chinese government, and some observers felt the WHO's statement was premature.^[22] Other scientists found the report convincing, and said there was no evidence of a laboratory origin for the virus.^[96][14]

WHO Director-General Tedros Adhanom stated that the team had experienced difficulty accessing raw data on early COVID-19 cases and that the least likely hypothesis, a lab leak, required additional investigation because "further data and studies will be needed to reach more robust conclusions".^[35][38][98] The leader of the WHO investigatory team, Peter Ben Embarek, said "An employee of the lab gets infected while working in a bat cave collecting samples. Such a scenario, while being a lab leak, would also fit our first hypothesis of direct transmission of the virus from bat to human."^[99]

The United States, European Union, and 13 other countries criticized the WHO-convened study, calling for transparency from the Chinese government and access to the raw data and original samples.^[100] Chinese officials described these criticisms as "an attempt to politicise the study".^[101] Scientists involved in the WHO report, including Liang Wannian, John Watson, and Peter Daszak, objected to the criticism, and said that the report was an example of the collaboration and dialogue required to successfully continue investigations into the matter.^[101]

On 15 July 2021, WHO Director-General Tedros Adhanom Ghebreyesus said that the COVID-19 lab leak theory had been prematurely discarded by the WHO, following his earlier statements that a potential leak requires "further investigation, potentially with additional missions involving specialist experts".^[102] He proposed a second phase of WHO investigation, which he said should take a closer look at the lab leak idea, and asked the Chinese government to be "transparent" and release relevant data.^[103] Later on 17 July, Tedros called for "audits of relevant laboratories and research institutions" in the area of the initial COVID-19 cases.^[104] China's government refused saying it showed "disrespect" and "arrogance towards science".^{[105][103][106]} The United States criticised China's position on the follow-up origin probe as "irresponsible" and "dangerous".^[107]

In June 2022, the WHO's Scientific Advisory Group for Origins of Novel Pathogens (SAGO) published a preliminary report urged a deeper investigation into the possibility of a laboratory leak.^[108] The SAGO chair said in a press conference that "the strongest evidence is still around a zoonotic transmission".^[109] The AP described the report as a "sharp reversal" of the WHO's previous assessment,^[108] and Science.org described reactions from academics as mixed.^[109]

In early 2023, the WHO abandoned its original investigation into the origin of SARS-CoV-2, delegating work to its standing committee, the Scientific Advisory Group for Origins of Novel Pathogens (SAGO). This work will attempt to establish a COVID-19 timeline, search for similar viruses, and conduct further laboratory studies on animals and human samples.^[110]

Mojiang copper mine

Members of DRASTIC, a collection of internet activists advocating for the lab leak theory,^[111][112] have raised concerns over a respiratory outbreak that happened in the spring of 2012 near an abandoned copper mine in China, which Shi Zhengli's group investigated. Shi's group collected a sample of viral RNA and named it RaBtCoV/4991.^[26] Later, Shi's group published a paper about a virus named RaTG13 in Nature in February 2020.^[113] Via sequence comparisons, it became clear that RaBtCoV/4991 and RaTG13 were likely the same virus. Shi has said that the renaming was done to reflect the origin location and year of the virus.^[114]

Some proponents, including Nicholas Wade and pseudonymous DRASTIC member "TheSeeker268", argued that the renaming was an attempt to obscure the origins of the virus and hide how it could be related to a laboratory origin of the related SARS-CoV-2 virus.^[115] Scientists have said that RaTG-13 is too distantly related to be connected to the pandemic's origins, and could not be altered in a laboratory to create SARS-CoV-2.^[116] Nature later published an addendum to the 2020 RaTG13 paper addressing any possible link to the mine, in which Shi says that the virus was collected there, but that it was very likely not the cause of the miners' illnesses. According to the addendum, laboratory tests conducted on the workers' serum were negative, and "no antibodies to a SARS-like coronavirus had been found."^[114]

Accidental release of a genetically modified virus

See also: Gain-of-function research § COVID-19 pandemic

One conspiracy theory spread in support a laboratory origin suggests SARS-CoV-2 was developed for gain-of-function research on coronaviruses.^[117] The exact meaning of "gain of function" is disputed among experts.^{[71][118][119]} According to emailed statements by Shi Zhengli, director of the Center for Emerging Infectious Diseases at the Wuhan Institute of Virology, her lab has not conducted any unpublished gain-of-function experiments on coronaviruses, and all WIV staff and students tested negative for the virus in the early days of the pandemic.^[120]

Furin cleavage site

 

Phylogenetic tree depicting the presence (red) or absence (black) of a furin cleavage site in various betacoronaviruses. From Wu et al.^[121]

One strand of argumentation in favor of a lab leak rests on the premise that there is something "unnatural" about the genetic makeup of the SARS-CoV-2 virus, showing it must have been created by genetic engineering.^[18] Some claims of bioengineering focus on the presence of two sequential cytosine-guanine-guanine (CGG) codons in the virus' RNA, more precisely in the crucial furin cleavage site.^[26][15] The CGG codon is one of several codons that translates into an arginine amino acid, and it is the least common arginine codon in human pathogenic betacoronaviruses.^[122] Partially, this lack of CGG codons in human pathogenic coronaviruses is due to natural selection; B-cells in the human body recognize areas on virus genomes where C and G are next to each other (so-called CpG islands).^[32][123] The CGG codon makes up 5% of the arginine codons in the SARS-CoV-1 genome, and it makes up 3% of the arginine codons in the SARS-CoV-2 genome.^[26]

Proponents of an engineered virus, including journalist Nicholas Wade, say that two such uncommon codons in a row are evidence for a laboratory experiment; because of the low chance of a CGG codon pair occurring in nature, and in contrast, the common usage of CGG codons for arginine in genetic engineering work.^[26][15] This has been debunked by scientists,^[124][125] who note that the CGG codon is also present (and even more frequent) in other coronaviruses, including MERS-CoV,^[126] and that a codon being rare does not mean it cannot be present naturally.^[125][127] If the CGG codon had been engineered into the virus, it should have mutated out of the virus as it circulated in humans in the wild over several years, but the opposite has occurred.^[127] In fact, the presence of the furin cleavage site, which is responsible for a significant increase in transmissibility, largely outweighs any disadvantageous immune responses from B-cells triggered by the genetic sequences which code for it.^[123][32]

Another source of speculation is the mere presence of the furin cleavage site.^[27][121] It is absent in the closest known relatives of SARS-CoV-2 (but present in other betacoronaviruses, e.g. BtHpCoV-ZJ13).^[128] This anomaly is most probably the result of recombination,^[121][129] and is further unsurprising since the genetic lineage of these viruses has not been adequately explored, sampled, or sequenced.^[130][131] A common occurrence among other coronaviruses (including MERS-CoV, HCoV-OC43, HCoV-HKU1, and appearing in near-identical fashion in HKU9-1), the site is preceded by short palindromic sequences suggestive of natural recombination caused by simple evolutionary mechanisms. Additionally, the suboptimal configuration and poor targeting of the cleavage site for humans or mice when compared with known examples (such as HCoV-OC43 or HCoV-HKU1), along with the complex and onerous molecular biology work this would have required, is inconsistent with what would be expected from an engineered virus.^[132]

Project DEFUSE was a rejected DARPA grant application, that proposed to sample bat coronaviruses from various locations in China.^[133] The rejected proposal document was leaked to the press by DRASTIC in September 2021.^[134] Co-investigators on the rejected proposal included the EcoHealth Alliance's Peter Daszak, Ralph Baric from UNC, Linfa Wang from Duke–NUS Medical School in Singapore, and Shi Zhengli from the Wuhan Institute of Virology.^[111] The grantees proposed to evaluate the ability of bat viruses to infect human cells in the laboratory using chimeric coronaviruses which were mutated in different locations, and to create protein-based vaccines out of the spike (S) protein (not the whole virus) which would be distributed to bats in the wild to reduce the chances of future human outbreaks.^[135] One proposed alteration was to modify bat coronaviruses to insert a cleavage site for the Furin protease at the S1/S2 junction of the spike (S) viral protein. There is no evidence that any genetic manipulation or reverse genetics (a technique required to make chimeric viruses) of SARS-related bat coronaviruses was ever carried out at the WIV.^[111][136] All available evidence points to the SARS-CoV-2 furin cleavage site being the result of natural evolution.^{[121][129][132]}

Political and government opinion

The situation reignited a debate over gain-of-function research, although the intense political rhetoric surrounding the issue has threatened to sideline serious inquiry over policy in this domain.^[137] Researchers have said the politicization of the debate is making the process more difficult, and that words are often twisted to become "fodder for conspiracy theories".^{[138][27][32]} The idea of an experiment conducted in 2015 on SARS-like coronaviruses being the source of the pandemic was reported in British tabloids early in the pandemic.^[139] Virologist Angela Rasmussen writes that this is unlikely, due to the intense scrutiny and government oversight gain-of-function research is subject to, and that it is improbable that research on hard-to-obtain coronaviruses could occur under the radar.^[73]

Kentucky Senator Rand Paul alleged that the US National Institutes of Health (NIH) had been funding gain-of-function research in Wuhan, accusing researchers including epidemiologist Ralph Baric of creating "super-viruses".^[118][71] Both Fauci and NIH Director Francis Collins denied that the US government supported such research.^{[118][119][140]} Baric likewise rejected Paul's allegations, saying his lab's research into cross-species transmission of bat coronaviruses did not qualify as gain-of-function.^[71] While a 2017 study of chimeric bat coronaviruses at the WIV listed NIH as a sponsor, NIH funding was only related to sample collection.^[71] A Washington Post fact-checker commented that "EcoHealth funding was not related to the experiments, but the collection of samples", and that "statements about Baric's research appear overblown".^[71] In October 2021, a spokesman for the NIH acknowledged that the EcoHealth Alliance had provided new data demonstrating that in a mouse experiment, a coronavirus had caused more weight loss than expected.^[141] This was described as an unexpected consequence of the research, and not its intended outcome or a component of the original funding proposal.^[142] Importantly, the NIH spokesman said this finding was provided in a late progress report, and was not available before prior statements about experiments at the WIV.^[143]

An August 2021 interim report authored by the minority staff of the Republican members of the US House Foreign Affairs Committee said that a laboratory leak origin for SARS-CoV-2 was more likely than a natural one.^[144][145] The report alleged that SARS-CoV-2 emerged in humans as a result of gain-of-function research made on the RaTG13 virus, collected in a cave in Yunnan province in 2012, which was afterwards accidentally released some time before 12 September 2019, when the database of the Wuhan Institute of Virology went offline.^[146][147] The August 2021 report relies mostly on existing public evidence, combined with internal documents from the CCP from before and during the early days of the pandemic.^[148] The interim report was published coinciding with a joint investigation from ProPublica and Vanity Fair.^[149][150] Immediately following its publication, the report was heavily criticized by experts in diplomacy and the Chinese language for mistranslations and misinterpretations of Chinese documents.^[151][152] Bacteriologist and lab leak theory proponent Richard Ebright criticized the report for packaging pre-existing and previously examined evidence as new information.^[144] Evolutionary biologist Michael Worobey commented that the document seemed to be either "a cynical effort to try to win Republican votes" in the November 2022 midterm elections, or "a bunch of staffers with no ability to understand the science who stumbled across a bunch of misinformation and disinformation-filled tweets."^[153] Virologist Angela Rasmussen described the report as "an embarrassingly bad use of taxpayer money and resources."^[144] The final version of the report was released on 18 April 2023. The final version reiterated the interim position that the pandemic began in a laboratory incident in the fall of 2019, based on what it called a "preponderance of circumstantial evidence".^[154]

Intelligence agencies

In the United States, several intelligence agencies have assessed the likelihood of a lab leak origin for SARS-CoV-2. Such assessments are not equivalent to scientific activity, but weigh the veracity of sources as the basis for making an intelligence report.^[155]

An August 2021 report made at the request of President Biden assessed that the Chinese government did not have foreknowledge of the COVID-19 outbreak.^[156] Overall, the report was not conclusive about the virus' origin. Of eight assembled teams, four (and the National Intelligence Council) were inclined, with low confidence, to uphold a zoonotic origin, three were unable to reach a conclusion and one (the FBI) supported, with moderate confidence, a lab leak.^{[157][158][159]} British intelligence agencies believe it is "feasible" that the virus began with a leak from a Chinese laboratory.^[160]

In February 2023, The Wall Street Journal reported that the US Energy Department, based on new intelligence, had shifted its view from "undecided" to "low confidence" that the pandemic originated with a lab leak.^{[161][162][163]} In the intelligence community, "low confidence" means the information is sourced to low-quality or otherwise untrustworthy sources.^[164] In the wake of these reports, FBI Director Christopher Wray reiterated the bureau's assessment, saying that the Government of China was doing its best to thwart any investigation.^[165][166] White House National Security Advisor Jake Sullivan responded to the report saying "some elements of the intelligence community have reached conclusions on one side, some on the other. A number of them have said they just don't have enough information to be sure", and there was still "no definitive answer" to the pandemic origins' question.^[162][167] The reassessment renewed the political debate around the issue in the US.^{[168][169][170]}

In June 2023, the Office of the Director of National Intelligence declassified their report on the virus' origins, in compliance with an Act of Congress compelling it to do so.^[171] The report stated that while the lab leak theory could not be ruled out, the overall assessment of the National Intelligence Council and a majority of IC assets (with low confidence) was that the pandemic most likely began as a zoonotic event.^[172][173] No evidence was found that SARS-CoV-2 or a progenitor virus existed in a laboratory, and there was no evidence of any biosafety incident.^[17] Proponents of the lab leak hypothesis reacted by accusing the agencies of conspiring with the Chinese, or of being incompetent.^[17] Covering the story for the Sydney Morning Herald, its science reporter Liam Mannix wrote that the US report marked the end of the lab leak case, and that it had ended "not with a bang, but a whimper".^[17][173]

Fringe views on genetic engineering

See also: COVID-19 misinformation § Gain-of-function research

The earliest known recorded mention of any type of lab leak theory appeared in the form of a tweet published on 5 January 2020, from a Hong Kong user named @GarboHK, insinuating that the Chinese government had created a new virus and intentionally released it.^[28][29] Similar ideas were later formalized in a preprint posted on BioRxiv on 31 January 2020, by researchers at the Indian Institute of Technology, claiming to find similarities between the new coronavirus' genome and that of HIV. The paper was quickly retracted due to irregularities in the researchers' "technical approach and...interpretation of the results".^[174][175] This claim was notably promoted by Luc Montagnier, a controversial French virologist and Nobel laureate, who contended that SARS-CoV-2 might have been created during research on a HIV/AIDS vaccine.^[176][177] Bioinformatics analyses show that the common sequences are short, that their similarity is insufficient to support the hypothesis of common origin, and that the identified sequences were independent insertions which occurred at varied points during the evolution of coronaviruses.^{[32][178][179]}

Further claims were promulgated by several anti-vaccine activists, such as Judy Mikovits and James Lyons-Weiler, who claimed that SARS-CoV-2 was created in a laboratory,^[180] with Mikovits going further and stating that the virus was both deliberately engineered and deliberately released.^[181][15] Weiler's analysis, where he argued that a long sequence in the middle of the spike protein of the virus was not found in other coronaviruses and was evidence for laboratory recombination, was dismissed by scientists, who found that the sequence in question was also found in many other coronaviruses, suggesting that it was "widely spread" in nature.^{[180][better source needed]}

Chinese researcher Li-Meng Yan was an early proponent of deliberate genetic engineering, releasing widely criticised preprint papers in favor of the lab leak theory in the spring of 2020.^[182][183] After she released her preprints, political operatives (including Steve Bannon and Guo Wengui) arranged for Yan to flee to the United States in the summer of 2020 to engage in a speaking tour on right-wing media outlets, as a method of distracting from the Trump administration's handling of the COVID-19 pandemic.^[184] According to scientific reviewers from the Johns Hopkins Center for Health Security, Yan's paper offered "contradictory and inaccurate information that does not support their argument,"^[183] while reviewers from MIT Press's Rapid Reviews: COVID-19 criticised her preprints as not demonstrating "sufficient scientific evidence to support [their] claims."^[182]

In September 2022, a panel assembled by The Lancet published a wide-ranging report on the pandemic, including commentary on the virus origin overseen by the group's chairman Jeffrey Sachs. This suggested that the virus may have originated from an American laboratory, a notion long-promoted by Sachs, including on the podcast of conspiracy theorist Robert F. Kennedy Jr. Reacting to this, virologist Angela Rasmussen commented that this may have been "one of The Lancet's most shameful moments regarding its role as a steward and leader in communicating crucial findings about science and medicine".^[185] Virologist David Robertson said the suggestion of US laboratory involvement was "wild speculation" and that "it's really disappointing to see such a potentially influential report contributing to further misinformation on such an important topic".^[185]

Deliberate release

Main article: COVID-19 misinformation § Bio-weapon

Historian of science Naomi Oreskes says that she does not know of any credible scientists who support the view that the virus was released deliberately, while the version proposing the virus may have escaped accidentally is more plausible.^[186]

In the United States, Senator Marsha Blackburn proposed a bill that would allow people to lodge lawsuits against China for use of a "biological weapon", stating that "China has a 5,000-year history of cheating and stealing. Some things will never change".^[187]

Developments in 2022

In June 2022, the WHO released a report advocating for more investigation into the lab leak theory.^[188] In response, Chinese Foreign Ministry spokesperson Zhao Lijian called the lab leak theory "a lie concocted by anti-China forces for political purposes, which has nothing to do with science".^[189]

In July 2022, two articles appeared in the journal Science analyzing all available epidemiological and genetic evidence from the earliest known cases in Wuhan.^[5] Based on two different analyses, the authors of both papers concluded that the outbreak began at the Huanan Seafood Wholesale Market and was unconnected to any laboratory. A third manuscript (a pre-print)^[190] examined RNA samples taken directly from the market in the spring of 2020 and detected SARS-CoV-2 RNA in environmental samples collected from animal stalls and sewage wells at the market.^[191][19] The RNA detected was highly similar to viruses which infected early outbreak patients who became sick after being present at the market.^[192][193] No virus was detected in any samples taken directly from animals at the market. University of Sydney virologist and co-author of both publications Edward C. Holmes commented that "The siren has definitely sounded on the lab leak theory" and "There's no emails. There's no evidence in any of the science. There's absolutely nothing".^[194]

Political, academic and media attention

The first media reports suggesting a SARS-CoV-2 lab leak appeared in the Daily Mail and The Washington Times in late January 2020.^[28] In a 31 January 2020 interview with Science Magazine, Professor Richard Ebright said there was a possibility that SARS-CoV-2 entered humans through a laboratory accident in Wuhan, and that all data on the genome sequence and properties of the virus were "consistent with entry into the human population as either a natural accident or a laboratory accident".^[195] A 5 February 2021 report from Caixin described these reports as rumors originating from two sources: a preprint paper by an Indian scholar posted to bioRxiv that was later withdrawn, and a BBC China report.^[196][197] On 8 February 2023, the acting director of the US National Institutes of Health (NIH) testified before a Republican-led House committee that the viruses studied in the Wuhan lab "bear no relationship" to SARS-CoV-2 and that suggesting equivalency would be akin to "saying that a human is equivalent to a cow".^[198]

In early 2021, the hypothesis returned to popular debate due to renewed media discussion.^[199] The renewed interest was prompted by two events. First, an article published in May by The Wall Street Journal reported that lab workers at the Wuhan Institute of Virology fell ill with COVID-19-like symptoms in November 2019. The report was based on off-the-record briefings with intelligence officials.^{[199][115][200]} The cases would precede official reports from the Chinese government stating the first known cases were in December 2019, although unpublished government data suggested the earliest cases were detected in mid-November.^[201][202] The Guardian stated that the WSJ article did little to confirm, in terms of good, quality evidence, the possibility of a lab leak;^[203] a declassified report from the National Intelligence Council likewise said that the fact the researchers were hospitalized was unrelated to the origins of the outbreak.^[204] Second, it was shown that Peter Daszak, the key organiser of the February 2020 statement in The Lancet, did not disclose connections to the Wuhan Institute of Virology.^{[34][199][115][205]} An addendum was later published by The Lancet, in which Daszak listed his previous cooperation with Chinese researchers.^[206]

After the publication of the WHO-convened report, politicians, talk show hosts, journalists, and some scientists advanced claims that SARS-CoV-2 may have come from the WIV.^[40] DRASTIC also contributed to its promotion, particularly via Twitter.^[207] In July 2021, a Harvard–Politico survey indicated that 52 percent of Americans believed that COVID-19 originated from a lab leak, while 28 percent believed that COVID-19 originated from an infected animal in nature.^[208] By March 2023, the percentage of Americans believing in lab origin had doubled (from 30% to 60%) since 3 years earlier, and the percentage of Americans believing in natural origins had halved (from 40% to 20%).^[209]

Science educationalist Heslley Machado Silva describes the idea of a China-produced virus as part of "xenophobic social network crusade" akin to a far-fetched movie scenario, which has nevertheless garnered many millions of internet adherents. Silva raises a plea for the pandemic to be a time for humanity to become "better and not an opportunity to foment hatred".^[210]

After May 2021, some media organizations softened previous language that described the laboratory leak theory as "debunked" or a "conspiracy theory".^[211] However, the prevailing scientific view remained that while an accidental leak was possible, it was highly unlikely.^[37][40]

China–US relations

See also: Chinese government response to COVID-19

The origin of COVID-19 became a source of friction in China–United States relations. The lab leak theory was promulgated in early 2020 by United States politicians and media, particularly US president Donald Trump, other prominent Republicans, and conservative media (such as Fox News pundit Tucker Carlson, and former Breitbart News publisher and White House chief strategist Steve Bannon).^[199][115] Trump had also referred to the virus as "kung flu",^[212] and the administration also expressed the intention to sanction China.^[213] In April 2020, Trump claimed to have evidence for the lab leak theory, but refused to produce it when requested.^[115][214] At that time, the media did not distinguish between the accidental lab leak of a natural virus and bio-weapon origin conspiracy theories. In online discussions, various theories – including the lab leak theory – were combined to form larger, baseless conspiracy plots.^[199] In May 2020, Fox News host Tucker Carlson accused Anthony Fauci of having "funded the creation of COVID" through gain-of-function research at the Wuhan Institute of Virology (WIV).^[118] Citing an essay by science writer Nicholas Wade, Carlson alleged that Fauci had directed research to make bat viruses more infectious to humans.^[140] Facebook enacted a policy to remove discussion of the lab leak theory as misinformation; it lifted the ban a year later, in May 2021.^{[34][215][216]}

A BBC China report stated that on 14 February, Chinese president Xi Jinping proposed for biosafety to be incorporated into law; the following day, new measures were introduced to "strengthen the management of laboratories", especially those working with viruses.^[196][197] In April 2020, The Guardian reported that China had taken steps to tightly regulate domestic research into the source of the outbreak in an attempt to control the narrative surrounding its origins and encourage speculation that the virus started outside the country.^[217] In May 2020, Chinese state media carried statements by scientists countering claims that the seafood market and Institute of Virology were possible origin sites, including comments by George Gao, director of the Chinese Center for Disease Control and Prevention.^[218]

In the United States, anti-China misinformation spread on social media, including baseless bio-weapon claims, fueled aggressive rhetoric towards people of Asian ancestry,^[219] and the bullying of scientists.^[40] Some scientists were worried their words would be misconstrued and used to support racist rhetoric.^[212] In a letter published in Science, a number of scientists, including Ralph S. Baric, argued that the accidental laboratory leak hypothesis had not been sufficiently investigated and remained possible, calling for greater clarity and additional data.^[220] Their letter was criticized by some virologists and public health experts, who said that a "hostile" and "divisive" focus on the WIV was unsupported by evidence, was impeding inquiries into legitimate concerns about China's pandemic response and transparency by combining them with speculative and meritless argument,^[26] and would cause Chinese scientists and authorities to share less rather than more data.^[40]

Some members of the Chinese government have promoted a counter-conspiracy theory claiming that SARS‑CoV‑2 originated in the U.S. military installation at Fort Detrick.^[221][222] This theory has little support. Chinese demands to investigate U.S. laboratories are thought to be a distracting technique to push focus away from Wuhan.^[223]

Chilling effects

See also: Lancet letter § Reception

According to Paul Thacker (writing for the British Medical Journal), some scientists and reporters said that "objective consideration of COVID-19's origins went awry early in the pandemic, as researchers who were funded to study viruses with pandemic potential launched a campaign labelling the lab leak hypothesis as a 'conspiracy theory.'"^[34] In February 2020, a letter was published in The Lancet authored by 27 scientists and spearheaded by Peter Daszak which described some alternate origin ideas as "conspiracy theories".^[224] Filippa Lentzos said some scientists "closed ranks" as a result, fearing for their careers and grants.^[34] The letter was criticized by Jamie Metzl for "scientific propaganda and thuggery",^[225] and by Katherine Eban as having had a "chilling effect" on scientific research and the scientific community by implying that scientists who "bring up the lab-leak theory ... are doing the work of conspiracy theorists".^[226][115]

Early in 2020, scientists including Jeremy Farrar, Kristian G. Andersen, and Robert F. Garry, among others, sent emails to Anthony Fauci with questions regarding the lab leak theory, and suspicions that some evidence supported it.^[227][228] NIH director Francis Collins was concerned at the time that discussion of the possibility could damage "international harmony".^[229] After the discovery of similar viruses in nature, more research into the genome, and the availability of more genomic sequences from the early days of the pandemic, these scientists publicly stated they supported the zoonotic theory as the most likely explanation.^{[230][231][14][232]}

Some journalists and scientists said they dismissed or avoided discussing the lab leak theory during the first year of the pandemic as a result of perceived polarization resulting from Donald Trump's embrace of the lab leak theory.^{[212][211][233][234]} The chair of the Board of Governors of the American Academy of Microbiology, Arturo Casadevall, said that, he (like many others) previously underestimated the lab leak hypothesis "mainly because the emphasis then [early in the pandemic] was on the idea of a deliberately engineered virus". However, by May 2021 it was a "long-simmering concern" in scientific circles, and that he perceived "greater openness" to it.^[235]

By fall 2022, most scientists were convinced, based on available evidence, that the pandemic most likely began with a natural zoonosis.^[6][14][16] The most likely natural reservoir is believed to reside in bats, with a possible intermediate host (such as palm civets,^[236][237] minks,^[238][237] or pangolins^[239][240]), before spillover into humans.^[241][242] In March 2023, James Alwine and colleagues argued that continuing to frame the lab leak hypothesis as being as likely as natural spillover was responsible for a misdirection of scientific effort, which could compromise progress towards preparing for future pandemics.^[43]

References

1. See numerous reliable sources which support this:
   
   • Pekar J (26 July 2022). "The molecular epidemiology of multiple zoonotic origins of SARS-CoV-2". Science. 377 (6609): 960–966. Bibcode:2022Sci...377..960P. doi:10.1126/science.abp8337. PMC 9348752. PMID 35881005.
   • Jiang X, Wang R (25 August 2022). "Wildlife trade is likely the source of SARS-CoV-2". Science. 377 (6609): 925–926. Bibcode:2022Sci...377..925J. doi:10.1126/science.add8384. PMID 36007033. S2CID 251843410. Retrieved 20 November 2022. Although the most probable reservoir animal for SARS-CoV-2 is Rhinolophus bats (2, 3), zoonotic spillovers likely involve an intermediate animal.
   • Holmes EC, Goldstein SA, Rasmussen AL, Robertson DL, Crits-Christoph A, et al. (September 2021). "The origins of SARS-CoV-2: A critical review". Cell (Review). 184 (19): 4848–4856. doi:10.1016/j.cell.2021.08.017. PMC 8373617. PMID 34480864. As for the vast majority of human viruses, the most parsimonious explanation for the origin of SARS-CoV-2 is a zoonotic event...There is currently no evidence that SARS-CoV-2 has a laboratory origin. There is no evidence that any early cases had any connection to the WIV, in contrast to the clear epidemiological links to animal markets in Wuhan, nor evidence that the WIV possessed or worked on a progenitor of SARS-CoV-2 prior to the pandemic.
   • Bolsen T, Palm R, Kingsland JT (October 2020). "Framing the Origins of COVID-19". Science Communication. 42 (5): 562–585. doi:10.1177/1075547020953603. ISSN 1075-5470. S2CID 221614695. Individuals may learn about the origins of COVID-19 through exposure to stories that communicate either what most scientists believe (i.e., zoonotic transmission) or through exposure to conspiratorial claims (e.g., the virus was created in a research laboratory in China).
   • Robertson L (2 March 2023). "Still No Determination on COVID-19 Origin". FactCheck.org. Retrieved 24 May 2023. most scientists suspect a zoonotic spillover in which the virus transferred from bats, or through an intermediate animal, to humans — the same way the SARS and MERS coronaviruses originated.
   • Gajilan AC (19 September 2021). "Covid-19 origins: Why the search for the source is vital". CNN. Retrieved 24 May 2023. The zoonotic hypothesis hinges on the idea that the virus spilled over from animals to humans, either directly through a bat, or through some other intermediary animal. Most scientists say that this is the likely origin, given that 75% of all emerging diseases have jumped from animals into humans.
   • McDonald J (28 June 2021). "Where Did COVID-19 Start? The Facts and Mysteries of Its Origin". NBC 5 Dallas-Fort Worth. Retrieved 24 May 2023. The default answer for most scientists has been that the virus, SARS-CoV-2, probably made the jump to humans from bats, if it was a direct spillover — or, more likely, through one or more intermediate mammals.
   • MCKEEVER A (6 April 2021). "We still don't know the origins of the coronavirus. Here are 4 scenarios". National Geographic. Retrieved 24 May 2023. The most controversial hypothesis for the origin of SARS-CoV-2 is also the one that most scientists agree is the least likely: that the virus somehow leaked out of a laboratory in Wuhan where researchers study bat coronaviruses.
   • Ball P. "Three years on, Covid lab-leak theories aren't going away. This is why". www.prospectmagazine.co.uk. The leading theory now backed by most scientists is that the virus arose in wild bats and found its way into animals (perhaps via a pangolin or a civet cat) sold at the Huanan Seafood Wholesale Market in Wuhan.
   • Jackson C (21 September 2020). "Controversy Aside, Why the Source of COVID-19 Matters". GEN - Genetic Engineering and Biotechnology News. Retrieved 24 May 2023. Most scientists studying the origins of COVID-19 have concluded that the SARS-CoV-2 virus probably evolved naturally and infected humans via incidental contact with a wild or domesticated animal.
   • McCarthy S (16 September 2021). "Bat-human virus spillovers may be very common, study finds". South China Morning Post. Retrieved 24 May 2023. Questions have been raised about whether the virus could have leaked from a laboratory studying related viruses in Wuhan – a scenario most scientists...feel is less likely than a natural spillover.
   • Danner C (26 May 2021). "Biden Joins the COVID Lab-Leak-Theory Debate". Intelligencer. Retrieved 24 May 2023. There continues to be no evidence at all for the conspiracy theory that SARS-CoV-2, the virus that causes COVID-19, was developed as some kind of bioweapon, and most scientists believe that the majority of available evidence indicates the virus jumped from animal to human.
2. Zimmer C, Mueller B (26 February 2022). "New Research Points to Wuhan Market as Pandemic Origin". The New York Times. Retrieved 13 June 2023.
3. Worobey M, Levy JI, Malpica Serrano L, Crits-Christoph A, Pekar JE, et al. (August 2022). "The Huanan Seafood Wholesale Market in Wuhan was the early epicenter of the COVID-19 pandemic". Science. 377 (6609): 951–959. Bibcode:2022Sci...377..951W. doi:10.1126/science.abp8715. PMC 9348750. PMID 35881010.
4. Pekar JE, Magee A, Parker E, Moshiri N, Izhikevich K, et al. (August 2022). "The molecular epidemiology of multiple zoonotic origins of SARS-CoV-2". Science. 377 (6609): 960–966. Bibcode:2022Sci...377..960P. doi:10.1126/science.abp8337. PMC 9348752. PMID 35881005.
5. There were two landmark origins studies published side-by-side in Science in July 2022:^[2]
   • Worobey et al. "The Huanan Seafood Wholesale Market in Wuhan was the early epicenter of the COVID-19 pandemic"^[3]
   • Pekar et al. "The molecular epidemiology of multiple zoonotic origins of SARS-CoV-2".^[4]
6. Jiang X, Wang R (25 August 2022). "Wildlife trade is likely the source of SARS-CoV-2". Science. 377 (6609): 925–926. Bibcode:2022Sci...377..925J. doi:10.1126/science.add8384. PMID 36007033. S2CID 251843410. Retrieved 20 November 2022.
7. Alkhovsky S, Lenshin S, Romashin A, Vishnevskaya T, Vyshemirsky O, Bulycheva Y, Lvov D, Gitelman A (9 January 2022). "SARS-like Coronaviruses in Horseshoe Bats (Rhinolophus spp.) in Russia, 2020". Viruses. 14 (1): 113. doi:10.3390/v14010113. PMC 8779456. PMID 35062318.
8. Frazzini S, Amadori M, Turin L, Riva F (7 October 2022). "SARS CoV-2 infections in animals, two years into the pandemic". Archives of Virology. 167 (12): 2503–2517. doi:10.1007/s00705-022-05609-1. PMC 9543933. PMID 36207554.
9. Fenollar F, Mediannikov O, Maurin M, Devaux C, Colson P, Levasseur A, Fournier P, Raoult D (1 April 2021). "Mink, SARS-CoV-2, and the Human-Animal Interface". Frontiers in Microbiology. Frontiers Media SA. 12: 663815. doi:10.3389/fmicb.2021.663815. ISSN 1664-302X. PMC 8047314. PMID 33868218.
10. Zhao J, Cui W, Tian B (2020). "The Potential Intermediate Hosts for SARS-CoV-2". Frontiers in Microbiology. 11: 580137. doi:10.3389/fmicb.2020.580137. ISSN 1664-302X. PMC 7554366. PMID 33101254.
11. Qiu X, Liu Y, Sha A (28 September 2022). "SARS-CoV-2 and natural infection in animals". Journal of Medical Virology. 95 (1): jmv.28147. doi:10.1002/jmv.28147. PMC 9538246. PMID 36121159.
12. Gupta SK, Minocha R, Thapa PJ, Srivastava M, Dandekar T (14 August 2022). "Role of the Pangolin in Origin of SARS-CoV-2: An Evolutionary Perspective". International Journal of Molecular Sciences. 23 (16): 9115. doi:10.3390/ijms23169115. PMC 9408936. PMID 36012377.
13. Suggestions for intermediate animal hosts between horseshoe bats (Rhinolophus spp.)^[7] and humans have included:
    • Common raccoon dog (Nyctereutes procyonoides)^[6]
    • American mink (Neogale vison)^[8][9]
    • Sunda pangolin (Manis javanica)^[10][11][12]
14. Holmes EC, Goldstein SA, Rasmussen AL, Robertson DL, Crits-Christoph A, et al. (September 2021). "The origins of SARS-CoV-2: A critical review". Cell (Review). 184 (19): 4848–4856. doi:10.1016/j.cell.2021.08.017. PMC 8373617. PMID 34480864. Under any laboratory escape scenario, SARS-CoV-2 would have to have been present in a laboratory prior to the pandemic, yet no evidence exists to support such a notion and no sequence has been identified that could have served as a precursor.
15. Gorski D (31 May 2021). "The origin of SARS-CoV-2, revisited". Science-Based Medicine. from the original on 1 June 2021. Retrieved 19 July 2021. The second [version of the lab leak] is the version that "reasonable" people consider plausible, but there is no good evidence for either version.
16. Holmes EC (14 August 2022). "The COVID lab leak theory is dead. Here's how we know the virus came from a Wuhan market". The Conversation. Retrieved 4 September 2022. For the lab leak theory to be true, SARS-CoV-2 must have been present in the Wuhan Institute of Virology before the pandemic started. This would convince me. But the inconvenient truth is there's not a single piece of data suggesting this. There's no evidence for a genome sequence or isolate of a precursor virus at the Wuhan Institute of Virology. Not from gene sequence databases, scientific publications, annual reports, student theses, social media, or emails. Even the intelligence community has found nothing. Nothing. And there was no reason to keep any work on a SARS-CoV-2 ancestor secret before the pandemic.
17. "COVID-19 lab leak theory ends with a whimper, not a bang". Sydney Morning Herald. 27 June 2023.
18. Lewandowsky S, Jacobs PH, Neil S (2023). "Chapter 2: Leak or Leap? Evidence and Cognition Surrounding the Origins of the SARS-CoV-2 Virus". In Butter M, Knight P (eds.). Covid Conspiracy Theories in Global Perspective. Taylor & Francis. pp. 26–39. doi:10.4324/9781003330769-2. ISBN 9781032359434.
19. Garry RF (10 November 2022). "The evidence remains clear: SARS-CoV-2 emerged via the wildlife trade". Proceedings of the National Academy of Sciences. 119 (47): e2214427119. Bibcode:2022PNAS..11914427G. doi:10.1073/pnas.2214427119. eISSN 1091-6490. ISSN 0027-8424. PMC 9704731. PMID 36355862. Most lab leak proponents don't mention that most major Chinese cities have one or more active coronavirus laboratories. The Chinese government established these laboratories after multiple spillovers of the first SARS-CoV in 2002 through 2004
20. Frutos R, Pliez O, Gavotte L, Devaux CA (May 2022). "There is no 'origin' to SARS-CoV-2". Environmental Research. 207: 112173. Bibcode:2022ER....207k2173F. doi:10.1016/j.envres.2021.112173. ISSN 0013-9351. PMC 8493644. PMID 34626592.
21. Maxmen A, Mallapaty S (8 June 2021). "The COVID lab-leak hypothesis: what scientists do and don't know". Nature. 594 (7863): 313–315. Bibcode:2021Natur.594..313M. doi:10.1038/d41586-021-01529-3. PMID 34108722. S2CID 235395594.
22. Dyer O (27 July 2021). "Covid-19: China stymies investigation into pandemic's origins". BMJ. 374: n1890. doi:10.1136/bmj.n1890. PMID 34315713. n1890.
23. Baker N (4 January 2021). "The Lab-Leak Hypothesis". New York Intelligencer. from the original on 20 January 2021. Retrieved 20 July 2021.
24. Jacobsen R (29 June 2021). "Inside the risky bat-virus engineering that links America to Wuhan". MIT Technology Review. from the original on 20 July 2021. Retrieved 20 July 2021. Ebright believes one factor at play was the cost and inconvenience of working in high-containment conditions. The Chinese lab's decision to work at BSL-2, he says, would have 'effectively increas[ed] rates of progress, all else being equal, by a factor of 10 to 20'.
25. Krishnaswamy S, Govindarajan TR (16 July 2021). "The controversy being created about the origins of the virus that causes COVID-19". Frontline. Chennai. from the original on 23 July 2021. Retrieved 30 July 2021.
26. Kasprak A (16 July 2021). "The 'Occam's Razor Argument' Has Not Shifted in Favor of a COVID Lab Leak". Snopes. from the original on 6 August 2021. Retrieved 24 July 2021.
27. Hakim MS (14 February 2021). "SARS-CoV-2, Covid-19, and the debunking of conspiracy theories". Reviews in Medical Virology. 31 (6): e2222. doi:10.1002/rmv.2222. PMC 7995093. PMID 33586302.
28. Kessler G (25 May 2021). "Timeline: How the Wuhan lab-leak theory suddenly became credible". The Washington Post. from the original on 25 July 2021. Retrieved 19 July 2021.
29. Bandeira L, Aleksejeva N, Knight T, Le Roux J. WEAPONIZED: HOW RUMORS ABOUT COVID-19'S ORIGINS LED TO A NARRATIVE ARMS RACE (PDF). The Atlantic Council. (PDF) from the original on 26 April 2022. Retrieved 17 January 2022.
30. Wallace-Wells B (27 May 2021). "The Sudden Rise of the Coronavirus Lab-Leak Theory". The New Yorker. from the original on 18 February 2022. Retrieved 17 January 2022.
31. Ruwitch J (31 March 2021). "Theory That COVID Came From A Chinese Lab Takes On New Life In Wake Of WHO Report". NPR. from the original on 2 December 2021. Retrieved 17 January 2022.
32. Frutos R, Gavotte L, Devaux CA (March 2021). "Understanding the origin of COVID-19 requires to change the paradigm on zoonotic emergence from the spillover to the circulation model". Infection, Genetics and Evolution. 95: 104812. doi:10.1016/j.meegid.2021.104812. PMC 7969828. PMID 33744401. The origin of SARS-Cov-2 is still passionately debated since it makes ground for geopolitical confrontations and conspiracy theories besides scientific ones...The marginal conspiracy theory of a voluntary released of an engineered virus forwarded by the press, blogs and politicians is not supported by any data.
33. "Covid origin: Why the Wuhan lab-leak theory is being taken seriously". BBC News. 27 May 2021. from the original on 30 June 2021. Retrieved 16 January 2022.
34. Thacker PD (8 July 2021). "The covid-19 lab leak hypothesis: Did the media fall victim to a misinformation campaign?". BMJ. 374: n1656. doi:10.1136/bmj.n1656. PMID 34244293. S2CID 235760734.
35. Miller J, Nebehay S (31 March 2021). "Data withheld from WHO team probing COVID-19 origins in China: Tedros". Reuters. from the original on 31 July 2021. Retrieved 31 July 2021.
36. Moritsugu K (22 July 2021). "China rebuffs WHO's terms for further COVID-19 origins study". Associated Press. from the original on 5 September 2021. Retrieved 6 September 2021. Zeng ... added that speculation that staff and graduate students at the lab had been infected and might have started the spread of the virus in the city was untrue.
37. See, for example, the following:
    News sources describing this as a majority view:
    • Maxmen A, Mallapaty S (8 June 2021). "The COVID lab-leak hypothesis: what scientists do and don't know". Nature. 594 (7863): 313–315. Bibcode:2021Natur.594..313M. doi:10.1038/d41586-021-01529-3. PMID 34108722. S2CID 235395594.
    • "The 'Occam's Razor Argument' Has Not Shifted in Favor of a Lab Leak". Snopes.com. 16 July 2021. from the original on 6 August 2021. Retrieved 18 July 2021. Shi's team concluded that SARS-CoV-2 was 79% identical to SARS-CoV-1 and 96% identical to a virus her team had sampled from bats in a mineshaft in 2013. This information formed the basis of the widely accepted conclusion that SARS-CoV-2's ancestor was a bat virus.
    • Ling J (15 June 2021). "The Lab Leak Theory Doesn't Hold Up". Foreign Policy. from the original on 1 July 2021. Retrieved 4 August 2021. Over the past year, I've spoken with a slew of researchers, scientists, and public health experts: Their takes on the origins of COVID-19 generally fall into two camps. Most say that the virus is very likely natural and that theories around the Wuhan Institute of Virology are a possible explanation, but they're unlikely. The other group, a minority, says both theories are more or less equally valid and that the lab leak theory is in desperate need of more study.
    • Sohn R (3 June 2021). "A Very Calm Guide to the Lab Leak Theory". Slate Magazine. from the original on 3 August 2021. Retrieved 4 August 2021. Most experts still tend to think the virus has a natural origin.
    
    Academic review articles which describe this as the mainstream view:
    • Adil MT, Rahman R, Whitelaw D, Jain V, Al-Taan O, Rashid F, Munasinghe A, Jambulingam P (February 2021). "SARS-CoV-2 and the pandemic of COVID-19". Postgraduate Medical Journal. 97 (1144): 110–116. doi:10.1136/postgradmedj-2020-138386. PMC 10016996. PMID 32788312. S2CID 221124011. the findings suggest that the laboratory incident hypothesis is extremely unlikely to explain introduction of the virus into the human population
    • Barh D, Silva Andrade B, Tiwari S, Giovanetti M, Góes-Neto A, Alcantara LC, Azevedo V, Ghosh P (September 2020). "Natural selection versus creation: a review on the origin of SARS-COV-2". Le Infezioni in Medicina (in Italian). Salerno. 28 (3): 302–311. PMID 32920565. from the original on 2 November 2020. Retrieved 15 June 2021. Conspiracy theories about a possible accidental leak from either of these laboratories known to be experimenting with bats and bat CoVs that has shown some structural similarity to human SARS-CoV-2 has been suggested, but largely dismissed by most authorities.
    • Graham RL, Baric RS (May 2020). "SARS-CoV-2: Combating Coronavirus Emergence". Immunity. 52 (5): 734–736. doi:10.1016/j.immuni.2020.04.016. PMC 7207110. PMID 32392464. the available data argue overwhelmingly against any scientific misconduct or negligence
    • Hakim MS (February 2021). "SARS-CoV-2, Covid-19, and the debunking of conspiracy theories". Reviews in Medical Virology. 31 (6): e2222. doi:10.1002/rmv.2222. PMC 7995093. PMID 33586302. Despite these massive online speculations, scientific evidence does not support this accusation of laboratory release theory...
    • Frutos R, Gavotte L, Devaux CA (March 2021). "Understanding the origin of COVID-19 requires to change the paradigm on zoonotic emergence from the spillover to the circulation model". Infection, Genetics and Evolution. 95: 104812. doi:10.1016/j.meegid.2021.104812. PMC 7969828. PMID 33744401.
38. Mallapaty S (15 April 2021). "After the WHO report: what's next in the search for COVID's origins". Nature. 592 (7854): 337–338. Bibcode:2021Natur.592..337M. doi:10.1038/d41586-021-00877-4. PMID 33790440. S2CID 232481786.
39. Zimmer C, Gorman J, Mueller B (27 May 2021). "Scientists Don't Want to Ignore the 'Lab Leak' Theory, Despite No New Evidence". The New York Times. from the original on 1 June 2021. Retrieved 18 July 2021.
40. Maxmen A (3 June 2021). "Divisive COVID 'lab leak' debate prompts dire warnings from researchers". Nature. 594 (7861): 15–16. Bibcode:2021Natur.594...15M. doi:10.1038/d41586-021-01383-3. PMID 34045757. S2CID 235232290.
41. Jacobsen R (13 May 2021). "Top researchers are calling for a real investigation into the origin of covid-19". MIT Technology Review. from the original on 4 August 2021. Retrieved 4 August 2021. The lab leak hypothesis has already become highly political. In the US, it has been embraced most loudly by Republican lawmakers and conservative media figures... The resulting polarization has had a chilling effect on scientists, some of whom have been reluctant to express their own concerns, says Relman.
42. Maxmen A (27 February 2022). "Wuhan market was epicentre of pandemic's start, studies suggest". Nature. 603 (7899): 15–16. Bibcode:2022Natur.603...15M. doi:10.1038/d41586-022-00584-8. PMID 35228730. S2CID 247168739.
43. Alwine JC, Casadevall A, Enquist LW, Goodrum FD, Imperiale MJ (March 2023). "A critical analysis of the evidence for the SARS-CoV-2 origin hypotheses". mSphere. 8 (2): e0036523. doi:10.1128/msphere.00119-23. PMC 10117112. PMID 36897078. S2CID 257429130.
44. Jones KE, Patel NG, Levy MA, Storeygard A, Balk D, Gittleman JL, Daszak P (February 2008). "Global trends in emerging infectious diseases". Nature. 451 (7181): 990–993. Bibcode:2008Natur.451..990J. doi:10.1038/nature06536. PMC 5960580. PMID 18288193.
45. Haider N, Rothman-Ostrow P, Osman AY, et al. (26 November 2020). "COVID-19—Zoonosis or Emerging Infectious Disease?". Frontiers in Public Health. 8: 596944. doi:10.3389/fpubh.2020.596944. PMC 7725765. PMID 33324602.
46. O'Keeffe J, Freeman S, Nicol A (21 March 2021). The Basics of SARS-CoV-2 Transmission. Vancouver: National Collaborating Centre for Environmental Health (NCCEH). ISBN 978-1-988234-54-0. from the original on 12 May 2021. Retrieved 12 May 2021.
47. Cohen J (January 2020). "Wuhan seafood market may not be source of novel virus spreading globally". Science. doi:10.1126/science.abb0611. S2CID 214574620. from the original on 27 January 2020. Retrieved 20 July 2021.
48. Eschner K (28 January 2020). "We're still not sure where the Wuhan coronavirus really came from". Popular Science. Archived from the original on 30 January 2020. Retrieved 30 January 2020.
49. Andersen KG, Rambaut A, Lipkin WI, Holmes EC, Garry RF (April 2020). "The proximal origin of SARS-CoV-2". Nature Medicine. 26 (4): 450–452. doi:10.1038/s41591-020-0820-9. PMC 7095063. PMID 32284615.
50. WHO-convened global study of origins of SARS-CoV-2: China Part (PDF) (Report). World Health Organization. 6 April 2021. pp. 7–10. (PDF) from the original on 25 June 2021. Retrieved 4 August 2021.
51. Lu R, Zhao X, Li J, Niu P, Yang B, Wu H, et al. (February 2020). "Genomic characterisation and epidemiology of 2019 novel coronavirus: implications for virus origins and receptor binding". The Lancet. 395 (10224): 565–574. doi:10.1016/S0140-6736(20)30251-8. PMC 7159086. PMID 32007145.
52. Cyranoski D (March 2020). "Mystery deepens over animal source of coronavirus". Nature. 579 (7797): 18–19. Bibcode:2020Natur.579...18C. doi:10.1038/d41586-020-00548-w. PMID 32127703.
53. Zhou P, Yang XL, Wang XG, Hu B, Zhang L, Zhang W, et al. (March 2020). "A pneumonia outbreak associated with a new coronavirus of probable bat origin". Nature. 579 (7798): 270–273. Bibcode:2020Natur.579..270Z. doi:10.1038/s41586-020-2012-7. PMC 7095418. PMID 32015507.
54. "Bat coronavirus isolate RaTG13, complete genome". Genebank. National Center for Biotechnology Information. 10 February 2020. from the original on 15 May 2020. Retrieved 5 March 2020.
55. Liu P, Jiang J, Wan X, Hua Y, Li L, Zhou J, Wang X, Hou F, Chen J, Zou J, Chen J (14 May 2020). "Are pangolins the intermediate host of the 2019 novel coronavirus (SARS-CoV-2)?". PLOS Pathogens. 16 (5): e1008421. doi:10.1371/journal.ppat.1008421. PMC 7224457. PMID 32407364.
56. Mallapaty S (24 September 2021). "Closest known relatives of virus behind COVID-19 found in Laos". Nature. 597 (7878): 603. Bibcode:2021Natur.597..603M. doi:10.1038/d41586-021-02596-2. PMID 34561634. S2CID 237626322.
57. Zhou P, Yang X, Wang X, Hu B, Zhang L, Zhang W, Si H, Zhu Y, Li B, Huang C, Chen H (December 2020). "Addendum: A pneumonia outbreak associated with a new coronavirus of probable bat origin". Nature. 588 (7836): E6. Bibcode:2020Natur.588E...6Z. doi:10.1038/s41586-020-2951-z. PMC 9744119. PMID 33199918. S2CID 226984973.
58. Zhou H, Ji J, Chen X, Bi Y, Li J, Wang Q, et al. (June 2021). "Identification of novel bat coronaviruses sheds light on the evolutionary origins of SARS-CoV-2 and related viruses". Cell Host & Microbe. 29 (7): 1031–1033. doi:10.1016/j.cell.2021.06.008. PMC 8188299. PMID 34147139.
59. Singh D, Yi SV (April 2021). "On the origin and evolution of SARS-CoV-2". Experimental & Molecular Medicine. Seoul. 53 (4): 537–547. doi:10.1038/s12276-021-00604-z. ISSN 1226-3613. PMC 8050477. PMID 33864026.
60. Zhu Z, Meng K, Meng G (December 2020). "Genomic recombination events may reveal the evolution of coronavirus and the origin of SARS-CoV-2". Scientific Reports. 10 (1): 21617. Bibcode:2020NatSR..1021617Z. doi:10.1038/s41598-020-78703-6. PMC 7728743. PMID 33303849.
61. Goraichuk IV, Arefiev V, Stegniy BT, Gerilovych AP (September 2021). "Zoonotic and Reverse Zoonotic Transmissibility of SARS-CoV-2". Virus Research. 302: 198473. doi:10.1016/j.virusres.2021.198473. PMC 8188804. PMID 34118360.
62. MacLean OA, Lytras S, Weaver S, Singer JB, Boni MF, Lemey P, Kosakovsky Pond SL, Robertson DL (12 March 2021). "Natural selection in the evolution of SARS-CoV-2 in bats created a generalist virus and highly capable human pathogen". PLOS Biology. 19 (3): e3001115. doi:10.1371/journal.pbio.3001115. PMC 7990310. PMID 33711012.
63. Kumar S, Tao Q, Weaver S, Sanderford M, Caraballo-Ortiz MA, Sharma S, Pond SL, Miura S (4 May 2021). "An Evolutionary Portrait of the Progenitor SARS-CoV-2 and Its Dominant Offshoots in COVID-19 Pandemic". Molecular Biology and Evolution. 38 (8): 3046–3059. doi:10.1093/molbev/msab118. PMC 8135569. PMID 33942847.
64. Pekar J, Worobey M, Moshiri N, Scheffler K, Wertheim JO (23 April 2021). "Timing the SARS-CoV-2 index case in Hubei province". Science. 372 (6540): 412–417. Bibcode:2021Sci...372..412P. doi:10.1126/science.abf8003. PMC 8139421. PMID 33737402. This analysis pushes human-to-human transmission back to mid-October to mid-November of 2019 in Hubei Province, China, with a likely short interval before epidemic transmission was initiated.
65. To KK, Sridhar S, Chiu KH, Hung DL, Li X, Hung IF, Tam AR, et al. (22 March 2021). "Lessons learned 1 year after SARS-CoV-2 emergence leading to COVID-19 pandemic". Emerging Microbes & Infections. Shanghai / London. 10 (1): 507–535. doi:10.1080/22221751.2021.1898291. PMC 8006950. PMID 33666147. We predicted in 2007 that 'the presence of a large reservoir of SARS-CoV-like viruses ... together with the culture of eating exotic mammals ... is a time bomb. The possibility of the reemergence of SARS and other novel viruses from animals or laboratories ... should not be ignored'.
66. Huang C, Wang Y, Li X, Ren L, Zhao J, Hu Y, et al. (February 2020). "Clinical features of patients infected with 2019 novel coronavirus in Wuhan, China". The Lancet. 395 (10223): 497–506. doi:10.1016/S0140-6736(20)30183-5. PMC 7159299. PMID 31986264.
67. Chen N, Zhou M, Dong X, Qu J, Gong F, Han Y, et al. (February 2020). "Epidemiological and clinical characteristics of 99 cases of 2019 novel coronavirus pneumonia in Wuhan, China: a descriptive study". The Lancet. 395 (10223): 507–513. doi:10.1016/S0140-6736(20)30211-7. PMC 7135076. PMID 32007143.
68. Xiao X, Newman C, Buesching CD, Macdonald DW, Zhou Z (7 June 2021). "Animal sales from Wuhan wet markets immediately prior to the COVID-19 pandemic". Scientific Reports. 11 (1): 11898. Bibcode:2021NatSR..1111898X. doi:10.1038/s41598-021-91470-2. PMC 8184983. PMID 34099828.
69. Li W, Shi Z, Yu M, Ren W, Smith C, Epstein JH, Wang H, et al. (28 October 2005). "Bats Are Natural Reservoirs of SARS-Like Coronaviruses". Science. 310 (5748): 676–679. Bibcode:2005Sci...310..676L. doi:10.1126/science.1118391. PMID 16195424. S2CID 2971923. Further studies in field epidemiology, laboratory infection, and receptor distribution and usage are being conducted to assess potential roles played by different bat species in SARS emergence.
70. "Coronavirus: Was US money used to fund risky research in China?". BBC News. 2 August 2021. from the original on 7 August 2021. Retrieved 8 August 2021.
71. Kessler G (18 May 2021). "Analysis - Fact-checking the Paul-Fauci flap over Wuhan lab funding". The Washington Post. from the original on 6 July 2021. Retrieved 19 July 2021.
72. Menachery VD, Yount BL, Debbink K, Agnihothram S, Gralinski LE, Plante JA, Graham RL, Scobey T, Ge X, Donaldson EF, Randell SH (9 November 2015). "A SARS-like cluster of circulating bat coronaviruses shows potential for human emergence". Nature Medicine. 21 (12): 1508–1513. doi:10.1038/nm.3985. PMC 4797993. PMID 26552008.
73. Rasmussen AL (January 2021). "On the origins of SARS-CoV-2". Nature Medicine. 27 (1): 9. doi:10.1038/s41591-020-01205-5. PMID 33442004.
74. "Reply to Science Magazine" (PDF). sciencemag.org: 9. (PDF) from the original on 6 December 2020. Retrieved 12 November 2020.
75. Stacey K (28 May 2021). "Covid-19 Lab-Leak Theory Puts Wuhan Research in Spotlight". Financial Times. from the original on 4 September 2021. Retrieved 9 September 2021. BSL-2 facilities are usually used for work of only moderate risk, where researchers can experiment at open benches wearing only lab coats and gloves. 'If this work was happening, it should definitely not have been happening at BSL-2,' said Ebright. 'That is roughly equivalent to a standard dentist office.'
76. Cortez MF (27 June 2021). "The Last—And Only—Foreign Scientist in the Wuhan Lab Speaks Out". Bloomberg News. from the original on 3 July 2021. Retrieved 3 August 2021. There were strict protocols and requirements aimed at containing the pathogens being studied, Anderson said... The Wuhan Institute of Virology is large enough that Anderson said she didn't know what everyone was working on at the end of 2019.
77. Yu W, Tang G, Zhang L, T Corlett R (2020). "Decoding the evolution and transmissions of the novel pneumonia coronavirus (SARS-CoV-2 / HCoV-19) using whole genomic data". Zoological Research. Kunming, Yunnan. 41 (3): 247–257. doi:10.24272/j.issn.2095-8137.2020.022. PMC 7231477. PMID 32351056.
78. Knapton S (22 February 2022). "Wuhan lab leak believed 'behind closed doors' to be likeliest origin of Covid, expert says". The Telegraph. Archived from the original on 22 February 2022. Retrieved 25 February 2022.
79. Artika IM, Ma'roef CN (May 2017). "Laboratory biosafety for handling emerging viruses". Asian Pacific Journal of Tropical Biomedicine. Hong Kong. 7 (5): 483–491. doi:10.1016/j.apjtb.2017.01.020. PMC 7103938. PMID 32289025.
80. "Infections caught in laboratories are surprisingly common". The Economist. 24 August 2021. from the original on 25 February 2022. Retrieved 25 February 2022.
81. Cyranoski D (1 February 2017). "Inside the Chinese lab poised to study world's most dangerous pathogens". Nature. 542 (7642): 399–400. Bibcode:2017Natur.542..399C. doi:10.1038/nature.2017.21487. PMID 28230144. S2CID 4399920.
82. Parry J (2004). "Breaches of safety regulations are probable cause of recent SARS outbreak, WHO says". World Health Organization. 328 (7450): 1222. doi:10.1136/bmj.328.7450.1222-b. PMC 416634. PMID 15155496.
83. "Guidelines for Safe Work Practices in Human and Animal Medical Diagnostic Laboratories". www.cdc.gov. MMWR CDC. from the original on 8 March 2022. Retrieved 11 March 2022. The more that laboratorians become aware of and adhere to recommended, science-based safety precautions, the lower the risk...incidents such as minor scrapes or cuts, insignificant spills, or unrecognized aerosols occur even more frequently and might not cause an exposure that results in an LAI. In this report, "laboratory exposures" refer to events that put employees at risk for an LAI and events that result in actual acquisition of LAIs...The first four routes [parenteral inoculations, spills and splashes onto skin, ingestion, animal bites and scratches] are relatively easy to detect, but they account for <20% of all reported LAIs
84. Begley S. "U.S. Lifts Moratorium on Funding Controversial, High-Risk Virus Research". Scientific American. from the original on 11 March 2022. Retrieved 11 March 2022.
85. Willman D, Muller M (26 August 2021). "A science in the shadows". Washington Post. from the original on 5 March 2022. Retrieved 11 March 2022.
86. "Outbreak Deja Vu: Rumor, Conspiracies, Folklore Link Disease Narratives". www.wbur.org. from the original on 14 April 2022. Retrieved 11 March 2022.
87. Leonard M, Philippe FL (2021). "Conspiracy Theories: A Public Health Concern and How to Address It". Frontiers in Psychology. 12: 682931. doi:10.3389/fpsyg.2021.682931. PMC 8355498. PMID 34393910.
88. Gorski DH (1 August 2022). "The rise and fall of the lab leak hypothesis for the origin of SARS-CoV-2". Science-Based Medicine.
89. Perng W, Dhaliwal SK (May 2022). "Anti-Asian Racism and COVID-19: How It Started, How It Is Going, and What We Can Do". Epidemiology. 33 (3): 379–382. doi:10.1097/EDE.0000000000001458. PMC 8983612. PMID 34954709. Since the early days of the pandemic, politicians promoted the unsubstantiated hypothesis the virus was developed in a laboratory in Wuhan, referring to COVID-19 as 'foreign,' 'Chinese,' and 'the Kung Flu.' Use of such language led to an 800% increase of these racist terms on social media and news outlets, and redirected fear and anger in a manner that reinforced racism and xenophobia.
90. Li Y, Nicholson HL (February 2021). "When "model minorities" become "yellow peril"-Othering and the racialization of Asian Americans in the COVID-19 pandemic". Sociol Compass. 15 (2): e12849. doi:10.1111/soc4.12849. PMC 7995194. PMID 33786062.
91. Cooper F, Dolezal L, Rose A. "Chapter 3: Coughing while Asian: Shame and Racialized Bodies". COVID-19 and Shame – Political Emotions and Public Health in the UK. Bloomsbury. ISBN 9781350283404.
92. Birchall C, Knight P (2023). "Chapter 24: A Perfect Storm – Covid-19 Conspiracy Theories in the United States". In Butter M, Knight P (eds.). Covid Conspiracy Theories in Global Perspective. Taylor & Francis. pp. 335–350. doi:10.4324/9781003330769-2. ISBN 9781032359434.
93. McKie R (22 August 2021). "The Wuhan lab leak theory is more about politics than science". The Guardian. from the original on 5 September 2021. Retrieved 6 September 2021.
94. "Former CDC director believes coronavirus came from lab in China". CNN Video. 26 March 2021. from the original on 25 July 2021. Retrieved 2 August 2021. One of them is in the lab, and one of them, which is the more likely, ... is that it likely was below the radar screen in China, spreading in the community ... which allowed it, when it first got recognized clinically, to be pretty well adapted.
95. Goldstein S (5 April 2021). "Op-Ed: Why Redfield Is Wrong on SARS-CoV-2 Origins". MedPage Today. from the original on 2 August 2021. Retrieved 2 August 2021.
96. Maxmen A (8 April 2021). "WHO report into COVID pandemic origins zeroes in on animal markets, not labs". Nature. 592 (7853): 173–174. Bibcode:2021Natur.592..173M. doi:10.1038/d41586-021-00865-8. PMID 33785930. S2CID 232429241.
97. Huang Y (31 March 2021). "What the WHO Investigation Reveals About the Origins of COVID-19 — And About the Vulnerabilities of the System Protecting Global Health". Foreign Affairs. from the original on 3 June 2021. Retrieved 15 June 2021. In 2004, SARS twice escaped a Beijing lab ... Chinese scientists have identified lax biosafety regulation as a concern even in high-level biosafety labs such as the Wuhan Institute.
98. "WHO Director-General's remarks at the Member State Briefing on the report of the international team studying the origins of SARS-CoV-2". World Health Organization. 30 March 2021. from the original on 25 April 2021. Retrieved 31 July 2021.
99. "WHO scientist puts COVID lab leak theory back under spotlight". Al Jazeera. 13 August 2021. from the original on 13 August 2021. Retrieved 14 August 2021.
100. Gan N (31 March 2021). "14 countries and WHO chief accuse China of withholding data from coronavirus investigation". CNN. from the original on 3 June 2021. Retrieved 31 May 2021.
101. Zarocostas J (10 April 2021). "Calls for transparency after SARS-CoV-2 origins report". The Lancet. 397 (10282): 1335. doi:10.1016/S0140-6736(21)00824-2. PMC 8032220. PMID 33838748. S2CID 233186234. Health diplomats speaking on condition of anonymity said that senior Chinese officials viewed the statements as an attempt to politicise the study.
102. "Following report, WHO chief calls for deeper probe into lab-leak theory on Covid-19 origins". France 24. 30 March 2021. from the original on 31 May 2021. Retrieved 6 August 2021.
103. Westcott B, Yee I, Xiong Y (22 July 2021). "Chinese government rejects WHO plan for second phase of Covid-19 origins study". CNN. from the original on 23 July 2021. Retrieved 23 July 2021.
104. Cohen J (17 July 2021). "With call for 'raw data' and lab audits, WHO chief pressures China on pandemic origin probe". Science. doi:10.1126/science.abl4763 (inactive 1 August 2023). from the original on 24 July 2021. Retrieved 1 August 2021.{{cite journal}}: CS1 maint: DOI inactive as of August 2023 (link)
105. "China slams WHO plan to audit Wuhan lab in study of Covid-19 origins". France 24. 22 July 2021. from the original on 1 August 2021. Retrieved 1 August 2021.
106. Buckley C (22 July 2021). "China denounces the W.H.O.'s call for another look at the Wuhan lab as 'shocking' and 'arrogant.'". The New York Times. from the original on 22 July 2021. Retrieved 23 July 2021.
107. "Covid: China rejects WHO plan for second phase of virus origin probe". BBC News. 23 July 2021. from the original on 30 July 2021. Retrieved 6 August 2021.
108. "WHO 'open' to probing 'new evidence' of COVID-19 lab leak origin theory, accepts 'key pieces of data' still missing". CBS News. Associated Press. 10 June 2022. from the original on 11 June 2022. Retrieved 19 June 2022.
109. Cohen J. "From 'open-minded' to 'underwhelming,' mixed reactions greet latest COVID-19 origin report". www.science.org. from the original on 12 June 2022. Retrieved 23 June 2022.
110. Mallapaty S (February 2023). "WHO abandons plans for crucial second phase of COVID-origins investigation". Nature. doi:10.1038/d41586-023-00283-y. PMID 36788278. S2CID 256870357.
111. Kormann C (12 October 2021). "The Mysterious Case of the COVID-19 Lab-Leak Theory". The New Yorker. from the original on 28 October 2021. Retrieved 29 October 2021. In 2018, Daszak, at EcoHealth Alliance, in partnership with Shi, Baric, and Wang, had submitted a $14.2-million grant proposal to the U.S. Defense Advanced Research Projects Agency (DARPA)....Andersen emphasized that there is no evidence to suggest that any of the work described in the proposal was actually done...@TheSeeker268 is a member of drastic, or Decentralized Radical Autonomous Search Team Investigating covid-19, which formed on Twitter and has been among the most aggressive advocates of the lab-leak theory.
112. Kannan R (6 June 2021). "Online group digs deeper into coronavirus leak theory". The Hindu. from the original on 8 June 2021. Retrieved 8 June 2021.
113. Zhou P, Yang XL, Wang XG, Hu B, Zhang L, et al. (March 2020). "A pneumonia outbreak associated with a new coronavirus of probable bat origin". Nature. 579 (7798): 270–273. Bibcode:2020Natur.579..270Z. doi:10.1038/s41586-020-2012-7. PMC 7095418. PMID 32015507.
114. Zhou P, Yang XL, Wang XG, Hu B, Zhang L, et al. (December 2020). "Addendum: A pneumonia outbreak associated with a new coronavirus of probable bat origin". Nature (Erratun). 588 (7836): E6. Bibcode:2020Natur.588E...6Z. doi:10.1038/s41586-020-2951-z. PMC 9744119. PMID 33199918.
115. Eban K (3 June 2021). "The Lab-Leak Theory: Inside the Fight to Uncover COVID-19's Origins". Vanity Fair. from the original on 6 June 2021. Retrieved 19 July 2021.
116. Frutos R, Javelle E, Barberot C, Gavotte L, Tissot-Dupont H, Devaux CA (March 2022). "Origin of COVID-19: Dismissing the Mojiang mine theory and the laboratory accident narrative". Environmental Research. 204 (Pt B): 112141. Bibcode:2022ER....204k2141F. doi:10.1016/j.envres.2021.112141. ISSN 0013-9351. PMC 8490156. PMID 34597664.
117. Thakur N, Das S, Kumar S, Maurya VK, Dhama K, et al. (December 2022). "Tracing the origin of Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2): A systematic review and narrative synthesis". J Med Virol. 94 (12): 5766–5779. doi:10.1002/jmv.28060. PMC 9538017. PMID 35945190. ... this accomplished hardly anything to halt the proliferation of often paradoxical and, at times, completely absurd conspiracy theories that propagated more rapidly than the disease outbreak itself. For example, it has been claimed that SARS‐CoV‐2 was either the consequence of a laboratory error or was purposefully manufactured or it was produced for GoF investigations ...
118. Robertson L (21 May 2021). "The Wuhan Lab and the Gain-of-Function Disagreement". FactCheck.org. from the original on 8 June 2021. Retrieved 4 June 2021.
119. Bryant CC (25 June 2021). "How risky is 'gain of function' research? Congress scrutinizes China". The Christian Science Monitor. from the original on 6 July 2021. Retrieved 19 July 2021.
120. John Cohen (31 July 2021). "Wuhan coronavirus hunter Shi Zhengli speaks out". Science. 369 (6503): 487–488. doi:10.1126/science.369.6503.487. PMID 32732399. S2CID 220892287.
121. Wu Y, Zhao S (January 2021). "Furin cleavage sites naturally occur in coronaviruses". Stem Cell Research. 50: 102115. doi:10.1016/j.scr.2020.102115. PMC 7836551. PMID 33340798.
122. Gu H, Chu DK, Peiris M, Poon LL (14 May 2020). "Multivariate analyses of codon usage of SARS-CoV-2 and other betacoronaviruses". Virus Evolution. 6 (1): veaa032. doi:10.1093/ve/veaa032. ISSN 2057-1577. PMC 7223271. PMID 32431949.
123. Krieg AM, Yi A, Matson S, Waldschmidt TJ, Bishop GA, Teasdale R, Koretzky GA, Klinman DM (April 1995). "CpG motifs in bacterial DNA trigger direct B-cell activation". Nature. 374 (6522): 546–549. Bibcode:1995Natur.374..546K. doi:10.1038/374546a0. PMID 7700380. S2CID 4261304.
124. "The CGG CGG genetic sequence and furin cleavage sites also exist in naturally-occurring viruses; these features aren't evidence of genetic manipulation". Health Feedback. 6 May 2022. Retrieved 6 March 2023.
125. Grehan K, Kingston N (22 June 2021). "COVID lab-leak theory: 'rare' genetic sequence doesn't mean the virus was engineered". The Conversation. Retrieved 6 March 2023.
126. Hou W (December 2020). "Characterization of codon usage pattern in SARS-CoV-2". Virology Journal. 17 (1): 138. doi:10.1186/s12985-020-01395-x. PMC 7487440. PMID 32928234.
127. Holmes EC, Goldstein SA, Rasmussen AL, Robertson DL, Crits-Christoph A, Wertheim JO, Anthony SJ, Barclay WS, Boni MF, Doherty PC, Farrar J, Geoghegan JL, Jiang X, Leibowitz JL, Neil SJ, Skern T, Weiss SR, Worobey M, Andersen KG, Garry RF, Rambaut A (September 2021). "The origins of SARS-CoV-2: A critical review". Cell. 184 (19): 4848–4856. doi:10.1016/j.cell.2021.08.017. PMC 8373617. PMID 34480864. S2CID 237204970. The presence of two adjacent CGG codons for arginine in the SARS-CoV-2 furin cleavage site is similarly not indicative of genetic engineering. Although the CGG codon is rare in coronaviruses, it is observed in SARS-CoV, SARS-CoV-2, and other human coronaviruses at comparable frequencies (Maxmen and Mallapaty, 2021). Further, if low-fitness codons had been artificially inserted into the virus genome they would have been quickly selected against during SARS-CoV-2 evolution, yet both CGG codons are more than 99.8% conserved among the >2,300,000 near-complete SARS-CoV-2 genomes sequenced to date, indicative of strong functional constraints.
128. Fan Y, Zhao K, Shi Z, Zhou P (2 March 2019). "Bat Coronaviruses in China". Viruses. 11 (3): 210. doi:10.3390/v11030210. PMC 6466186. PMID 30832341.
129. Whittaker GR (October 2021). "SARS-CoV-2 spike and its adaptable furin cleavage site". The Lancet Microbe. 2 (10): e488–e489. doi:10.1016/S2666-5247(21)00174-9. PMC 8346238. PMID 34396356.
130. Ruiz-Aravena M, McKee C, Gamble A, Lunn T, Morris A, Snedden CE, Yinda CK, Port JR, Buchholz DW, Yeo YY, Faust C, Jax E, Dee L, Jones DN, Kessler MK, Falvo C, Crowley D, Bharti N, Brook CE, Aguilar HC, Peel AJ, Restif O, Schountz T, Parrish CR, Gurley ES, Lloyd-Smith JO, Hudson PJ, Munster VJ, Plowright RK (May 2022). "Ecology, evolution and spillover of coronaviruses from bats". Nature Reviews Microbiology. 20 (5): 299–314. doi:10.1038/s41579-021-00652-2. ISSN 1740-1534. PMC 8603903. PMID 34799704.
131. Wang W, Tian J, Chen X, Hu R, Lin X, Pei Y, Lv J, Zheng J, Dai F, Song Z, Chen Y, Zhang Y (29 June 2022). "Coronaviruses in wild animals sampled in and around Wuhan at the beginning of COVID-19 emergence". Virus Evolution. 8 (1): veac046. doi:10.1093/ve/veac046. PMC 9214087. PMID 35769892.
132. Holmes EC, Goldstein SA, Rasmussen AL, Robertson DL, Crits-Christoph A, Wertheim JO, Anthony SJ, Barclay WS, Boni MF, Doherty PC, Farrar J, Geoghegan JL, Jiang X, Leibowitz JL, Neil SJ, Skern T, Weiss SR, Worobey M, Andersen KG, Garry RF, Rambaut A (September 2021). "The origins of SARS-CoV-2: A critical review". Cell. 184 (19): 4848–4856. doi:10.1016/j.cell.2021.08.017. PMC 8373617. PMID 34480864. The SARS-CoV-2 furin cleavage site (containing the amino acid motif RRAR) does not match its canonical form (R-X-R/KR), is suboptimal compared to those of HCoV-HKU1 and HCoV-OC43, lacks either a P1 or P2 arginine (depending on the alignment), and was caused by an out-of-frame insertion...There is no logical reason why an engineered virus would utilize such a suboptimal furin cleavage site, which would entail such an unusual and needlessly complex feat of genetic engineering...Further, there is no evidence of prior research at the WIV involving the artificial insertion of complete furin cleavage sites into coronaviruses.
133. Federman DE (25 September 2021). "The Lab-Leak Debate Just Got Even Messier". The Atlantic. from the original on 29 October 2021. Retrieved 29 October 2021.{{cite news}}: CS1 maint: multiple names: authors list (link)
134. "Scientists Square Off Over Covid, Wuhan, and Peter Daszak". Undark Magazine. 24 November 2021. from the original on 29 December 2021. Retrieved 30 December 2021.
135. Zimmer C, Mueller B (21 October 2021). "Bat Research Group Failed to Submit Virus Studies Promptly, N.I.H. Says". The New York Times. from the original on 27 October 2021. Retrieved 29 October 2021.
136. Holmes EC, Goldstein SA, Rasmussen AL, Robertson DL, Crits-Christoph A, Wertheim JO, Anthony SJ, Barclay WS, Boni MF, Doherty PC, Farrar J, Geoghegan JL, Jiang X, Leibowitz JL, Neil SJ, Skern T, Weiss SR, Worobey M, Andersen KG, Garry RF, Rambaut A (September 2021). "The origins of SARS-CoV-2: A critical review". Cell. 184 (19): 4848–4856. doi:10.1016/j.cell.2021.08.017. PMC 8373617. PMID 34480864. Further, there is no evidence of prior research at the WIV involving the artificial insertion of complete furin cleavage sites into coronaviruses...No published work indicates that other methods, including the generation of novel reverse genetics systems, were used at the WIV to propagate infectious SARSr-CoVs based on sequence data from bats. Gain-of-function research would be expected to utilize an established SARSr-CoV genomic backbone, or at a minimum a virus previously identified via sequencing.
137. Zimmer C, Gorman J (20 June 2021). "Fight Over Covid's Origins Renews Debate on Risks of Lab Work". The New York Times. from the original on 28 October 2021. Retrieved 27 October 2021. Sorting out the balance of risks and benefits of the research has proved over the years to be immensely challenging. And now, the intensity of the politics and rhetoric over the lab leak theory threatens to push detailed science policy discussions to the sidelines. "It's just going to make it harder to get back to a serious debate," said Marc Lipsitch, an epidemiologist at the Harvard T.H. Chan School of Public Health who has urged the government to be more transparent about its support of gain-of-function research.
138. Smith M (18 June 2021). . Australian Financial Review. Sydney. Archived from the original on 13 July 2021. 'One of the problems we have as scientists is our words are co-opted by people who have a political agenda,' says Rodrigo. 'What we say can become fodder for conspiracy theories. This is not an issue of a particular country's problem. If the lab leak hypothesis is plausible and is shown to be true then this is an issue into how we manage labs and research facilities. It is not about China. It is about research facilities and how we manage that everywhere.'
139. Evans NG (26 August 2020). "Human Infection Challenge Studies: a Test for the Social Value Criterion of Research Ethics". mSphere. 5 (4). doi:10.1128/mSphere.00669-20. PMC 7364225. PMID 32669462.
140. Dapcevich M (20 May 2021). "Did Fauci Fund 'Gain of Function' Research, Thereby Causing COVID-19 Pandemic?". Snopes. from the original on 8 July 2021. Retrieved 19 July 2021.
141. "In Major Shift, NIH Admits Funding Risky Virus Research in Wuhan". Vanity Fair. 22 October 2021. from the original on 24 November 2021. Retrieved 27 November 2021.
142. "Was NIH-funded work on MERS virus in China too risky? Science examines the controversy". www.science.org. from the original on 28 November 2021. Retrieved 27 November 2021.
143. "NIH says grantee failed to report experiment in Wuhan that created a bat virus that made mice sicker". www.science.org. from the original on 27 November 2021. Retrieved 27 November 2021.
144. Mueller B, Zimmer C (27 October 2022). "G.O.P. Senator's Report on Covid Origins Suggests Lab Leak, but Offers Little New Evidence". The New York Times. Retrieved 29 October 2022.
145. "Senate GOP report argues lab-leak theory is most likely origin of covid". The Washington Post. ISSN 0190-8286. Retrieved 29 October 2022.
146. The Origins of COVID-19: an investigation of the Wuhan Institute of Virology (PDF). Washington D.C.: Michael T. McCaul/U.S. House Foreign Affairs Committee. 2021. (PDF) from the original on 26 August 2021. Retrieved 27 August 2021.
147. "The world needs a proper investigation into how covid-19 started". The Economist. 21 August 2021. from the original on 27 August 2021. Retrieved 27 August 2021.
148. Weixel N (28 October 2022). "Senate GOP report on COVID origin suggests lab leak is 'most likely'". The Hill. Retrieved 29 October 2022.
149. Eban K, Kao J (28 October 2022). "COVID-19 Origins: Investigating a 'Complex and Grave Situation' Inside a Wuhan Lab". ProPublica. Retrieved 28 February 2023.
150. Kao J, Eban K (28 October 2022). "COVID-19 Origins: Investigating a 'Complex and Grave Situation' Inside a Wuhan Lab". Vanity Fair. Retrieved 28 February 2023.
151. Tani M (31 October 2022). "ProPublica scrambles to check translation in COVID origin story". www.semafor.com. Retrieved 28 February 2023.
152. Paun C, Zeller S, Reader R, Leonard B, Scullion G (4 November 2022). "Cross-examining the lab-leak theorists". POLITICO. Retrieved 28 February 2023.
153. Cohen J (28 October 2022). "Republican Senate staff tout lab-leak theory of the pandemic's origin". Science.
154. Sasha Pezenik, Josh Margolin, Kaitlyn Morris, and Terry Moran (18 April 2023). "New report from Senate Republicans doubles down on COVID lab leak theory". ABC news. Retrieved 20 April 2023.{{cite news}}: CS1 maint: multiple names: authors list (link)
155. Rofer C (3 March 2023). "Lab-Leak Intelligence Reports Aren't Scientific Conclusions". Scientific American.
156. Nakashima E, Achenbach J (27 August 2021). "U.S. spy agencies rule out possibility the coronavirus was created as a bioweapon, say origin will stay unknown without China's help". The Washington Post. from the original on 29 August 2021. Retrieved 29 August 2021.
157. Merchant N (27 August 2021). "US intelligence still divided on origins of coronavirus". Associated Press. from the original on 29 August 2021. Retrieved 29 August 2021.
158. Cohen J (27 August 2021). "COVID-19's origins still uncertain, U.S. intelligence agencies conclude". Science. doi:10.1126/science.abm1388. S2CID 240981726. from the original on 31 August 2021. Retrieved 29 August 2021. The first, and most important, takeaway is that the IC is 'divided on the most likely origin' of the pandemic coronavirus and that both hypotheses are 'plausible.'
159. Barnes JE (29 October 2021). "Origin of Virus May Remain Murky, U.S. Intelligence Agencies Say". The New York Times. ISSN 0362-4331. from the original on 17 December 2021. Retrieved 17 December 2021.
160. Brown L (30 May 2021). "Covid: Wuhan lab leak is 'feasible', say British spies". The Sunday Times. from the original on 19 February 2022. Retrieved 19 February 2022.
161. Gordon MR, Strobel WP (26 February 2023). "Lab Leak Most Likely Origin of Covid-19 Pandemic, Energy Department Now Says". The Wall Street Journal. Retrieved 26 February 2023.
162. Mueller J (26 February 2023). "National security adviser: No 'definitive answer' on COVID lab leak". The Hill. Retrieved 26 February 2023.
163. Barnes JE (26 February 2023). "Lab Leak Most Likely Caused Pandemic, Energy Dept. Says". The New York Times. Retrieved 27 February 2023.
164. "How to make sense of intelligence leaks". The Economist (The Economist explains). 9 March 2023.
165. Kaur A, Diamond D (28 February 2023). "FBI director says covid-19 'most likely' originated from lab incident". Washington Post. Retrieved 1 March 2023.
166. "FBI chief Christopher Wray says China lab leak most likely". BBC News. 1 March 2023. Retrieved 5 June 2023.
167. LeBlanc P (27 February 2023). "New assessment on the origins of Covid-19 adds to the confusion". CNN. Retrieved 27 February 2023.
168. Smith D (28 February 2023). "'It's just gotten crazy': how the origins of Covid became a toxic US political debate". The Guardian.
169. Duff M (28 February 2023). "It's Not Case Closed on the Lab-Leak Theory". Slate. Retrieved 28 February 2023. The debate has gotten extraordinarily heated, with proponents of each accusing the other side of motivated reasoning.
170. Bettelheim A, Owens C, Reed T (27 February 2023). "New COVID lab leak assessment reignites furor over pandemic origins". Axios. Retrieved 28 February 2023.
171. Whitcomb D (24 June 2023). "No direct evidence COVID started in Wuhan lab, US intelligence report says". Reuters. Retrieved 25 June 2023.
172. "Intelligence report says US split on Covid-19 origins". BBC News. 24 June 2023. Retrieved 25 June 2023.
173. Merchant N (23 June 2023). "US intelligence report on COVID-19 origins rejects some points raised by lab leak theory proponents". ABC News. Retrieved 24 June 2023.
174. "Scientists slam Indian study that fueled coronavirus rumors". Nikkei Asia. from the original on 14 January 2022. Retrieved 11 January 2022.
175. "Quick retraction of a faulty coronavirus paper was a good moment for science". STAT. 3 February 2020. from the original on 7 January 2022. Retrieved 11 January 2022.
176. "French Nobel prize winner: 'Covid-19 was made in lab'". The Connexion. Monaco. 18 April 2020. from the original on 26 April 2020. Retrieved 1 September 2021.
177. "Le coronavirus, fabriqué à partir du virus du sida ? La thèse très contestée du professeur Montagnier". Le Monde (in French). 17 April 2020. from the original on 4 September 2021. Retrieved 1 September 2021.
178. Xiao C, Li X, Liu S, Sang Y, Gao S, Gao F (14 February 2020). "HIV-1 did not contribute to the 2019-nCoV genome". Emerging Microbes & Infections. Shanghai / London. 9 (1): 378–381. doi:10.1080/22221751.2020.1727299. PMC 7033698. PMID 32056509.
179. Liu S, Saif LJ, Weiss SR, Su L (26 February 2020). "No credible evidence supporting claims of the laboratory engineering of SARS-CoV-2". Emerging Microbes & Infections. Shanghai / London. 9 (1): 505–507. doi:10.1080/22221751.2020.1733440. PMC 7054935. PMID 32102621.
180. Hao P, Zhong W, Song S, Fan S, Li X (1 January 2020). "Is SARS-CoV-2 originated from laboratory? A rebuttal to the claim of formation via laboratory recombination". Emerging Microbes & Infections. 9 (1): 545–547. doi:10.1080/22221751.2020.1738279. PMC 7144200. PMID 32148173.
181. ENSERINK M (8 May 2022). "Fact-checking Judy Mikovits, the controversial virologist attacking Anthony Fauci in a viral conspiracy video". www.science.org.
182. Koyama T, Lauring A, Gallo RC, Reitz M (24 September 2020), "Reviews of 'Unusual Features of the SARS-CoV-2 Genome Suggesting Sophisticated Laboratory Modification Rather Than Natural Evolution and Delineation of Its Probable Synthetic Route'", Biological and Chemical Sciences, Rapid Reviews Infectious Diseases, Rapid Reviews: Covid-19, MIT Press, ISSN 2692-4072, from the original on 8 October 2020
183. Warmbrod KL, West RM, Connell ND, Gronvall GK (21 September 2020). In Response: Yan et al Preprint—Examinations of the Origin of SARS-CoV-2 (PDF) (Report). Johns Hopkins Center for Health Security. (PDF) from the original on 26 September 2020. Retrieved 26 September 2020.
184. Qin A, Wang V, Hakim D (20 November 2020). "How Steve Bannon and a Chinese Billionaire Created a Right-Wing Coronavirus Media Sensation". The New York Times. from the original on 30 April 2021. Retrieved 23 January 2022.
185. Kilander G (16 September 2022). "Lancet report claiming Covid could have come from US lab prompts anger". The Independent. Retrieved 31 October 2022.
186. Oreskes N (1 September 2021). "The Lab-Leak Theory of COVID's Origin Is Not Totally Irrational". Scientific American. from the original on 17 August 2021.
187. Barry S (2021). "Big Thunder, Little Rain: The Yellow Peril Framing of the Pandemic Campaign Against China". Chinese Journal of International Law. Oxford University Press (OUP). 20 (2): 395–424. doi:10.1093/chinesejil/jmab023. ISSN 1540-1650. PMC 8500121.
188. Smith A (10 June 2022). "WHO makes U-turn, urging further investigation on 'lab leak' theory in new Covid report". NBC News. from the original on 10 June 2022. Retrieved 10 June 2022.
189. "China calls COVID 'lab leak' theory a lie after WHO report". CP24. The Associated Press. 10 June 2022. from the original on 10 June 2022. Retrieved 10 June 2022.
190. Gao G, Liu W, Liu P, Lei W, Jia Z, He X, Liu L, Shi W, Tan Y, Zou S, Zhao X, Wong G, Wang J, Wang F, Wang G, Qin K, Gao R, Zhang J, Li M, Xiao W, Guo Y, Xu Z, Zhao Y, Song J, Zhang J, Zhen W, Zhou W, Ye B, Song J, Yang M, Zhou W, Bi Y, Cai K, Wang D, Tan W, Han J, Xu W, Wu G (25 February 2022), Surveillance of SARS-CoV-2 in the environment and animal samples of the Huanan Seafood Market, Research Square Platform LLC, doi:10.21203/rs.3.rs-1370392/v1
191. Courtier-Orgogozo V, de Ribera FA (November 2022). "SARS-CoV-2 infection at the Huanan seafood market". Environmental Research. 214 (Pt 1): 113702. Bibcode:2022ER....214k3702C. doi:10.1016/j.envres.2022.113702. ISSN 0013-9351. PMC 9220909. PMID 35752330.
192. da Silva SJ, do Nascimento JC, Germano Mendes RP, Guarines KM, Targino Alves da Silva C, da Silva PG, de Magalhães JJ, Vigar JR, Silva-Júnior A, Kohl A, Pardee K, Pena L (8 August 2022). "Two Years into the COVID-19 Pandemic: Lessons Learned". ACS Infectious Diseases. 8 (9): 1758–1814. doi:10.1021/acsinfecdis.2c00204. eISSN 2373-8227. ISSN 2373-8227. PMC 9380879. PMID 35940589.
193. Balloux F, Tan C, Swadling L, Richard D, Jenner C, Maini M, van Dorp L (1 January 2022). "The past, current and future epidemiological dynamic of SARS-CoV-2". Oxford Open Immunology. 3 (1): iqac003. doi:10.1093/oxfimm/iqac003. eISSN 2633-6960. PMC 9278178. PMID 35872966.
194. Mannix L (2 August 2022). "'The siren has sounded': Scientists pinpoint COVID's origin". Sydney Morning Herald.
195. Cohen J (31 January 2020). "Mining coronavirus genomes for clues to the outbreak's origins". Science. doi:10.1126/science.abb1256. S2CID 214373002.
196. "Dújiā | shízhènglì huíyīng zhíyí zhuānjiā yì zhì rènwéi xīnguān bìngdú fēi rénzào" 独家|石正丽回应质疑 专家一致认为新冠病毒非人造 [Exclusive | Shi Zhengli responds to doubts, experts agree that the new coronavirus is not man-made]. Caixin (in Zhuang). Beijing. 5 February 2020. from the original on 5 February 2020. Retrieved 20 July 2021.
197. "Xīnguān yìqíng: Wǔhàn yǐ zhī zuìzǎo quèzhěn bìnglì wèi 'yī míng 70 duō suì nǎo gěng huànzhě'" 模糊不清的'零号病人'与新冠病毒来源争议 [New Crown Epidemic: The earliest known confirmed case in Wuhan is 'a patient with cerebral infarction in his 70s']. BBC News 中文 (in Simplified Chinese). 18 February 2020. from the original on 2 March 2020. Retrieved 20 July 2021.
198. Stolberg SG (8 February 2023). . The New York Times. Archived from the original on 9 February 2023. Retrieved 11 February 2023.
199. Knight P (21 June 2021). "COVID-19: Why lab-leak theory is back despite little new evidence". The Conversation. Melbourne. from the original on 18 July 2021. Retrieved 18 July 2021.
200. Hinshaw MR (23 May 2021). "Intelligence on Sick Staff at Wuhan Lab Fuels Debate on Covid-19 Origin". Wall Street Journal. from the original on 25 July 2021. Retrieved 26 July 2021.{{cite news}}: CS1 maint: multiple names: authors list (link)
201. "First Covid-19 case happened in November, China government records show - report". The Guardian. 13 March 2020. from the original on 20 March 2020. Retrieved 26 July 2021.
202. Ma J (13 March 2020). "Coronavirus: China's First Confirmed Covid-19 Case Traced Back to November 17". South China Morning Post. Hong Kong. from the original on 13 March 2020. Retrieved 19 November 2021. The first case of someone in China suffering from Covid-19 ... can be traced back to November 17, according to government data seen by the South China Morning Post.
203. Beaumont P (27 May 2021). "Did Covid come from a Wuhan lab? What we know so far". The Guardian. from the original on 28 July 2021. Retrieved 26 July 2021.
204. Katie Bo Lillis (29 October 2021). "US Intelligence community releases full declassified report that does not determine origin of Covid-19". CNN. from the original on 29 October 2021. Retrieved 29 October 2021. The IC [intelligence community] assesses that information indicating that several WIV researchers reported symptoms consistent with COVID-19 in autumn 2019 is not diagnostic of the pandemic's origins. Even if confirmed, hospital admission alone would not be diagnostic of COVID-19 infection.
205. Spence M. "The rise and fall of British virus hunter Peter Daszak". The Times. from the original on 27 July 2021. Retrieved 26 July 2021.
206. Εditors of The Lancet (June 2021). "Addendum: competing interests and the origins of SARS-CoV-2". The Lancet. 397 (10293): 2449–2450. doi:10.1016/S0140-6736(21)01377-5. PMC 8215723. S2CID 235494625.
207. Ryan J (15 April 2021). "How the coronavirus origin story is being rewritten by a guerrilla Twitter group". CNET. from the original on 16 June 2021. Retrieved 1 June 2021.
208. Ollstein AM (9 July 2021). "POLITICO-Harvard poll: Most Americans believe Covid leaked from lab". Politico. Retrieved 13 September 2022.
209. "How the covid lab leak became the American public's predominant theory". The Washington Post.
210. Silva HM (June 2021). "The xenophobia virus and the COVID-19 pandemic". Ethique Sante. 18 (2): 102–106. doi:10.1016/j.etiqe.2021.03.002. PMC 9760352. PMID 36568643.
211. Stanage N (25 May 2021). "The Memo: Media face hard questions on Trump, Wuhan lab". The Hill. from the original on 3 June 2021. Retrieved 2 June 2021.
212. Chow D (16 June 2021). "The science around the lab leak theory hasn't changed. But here's why some scientists have". NBC News. from the original on 6 August 2021. Retrieved 27 July 2021.
213. Stein J, Leonnig CD, Dawsey J, Shih G (30 April 2020). "U.S. officials crafting retaliatory actions against China over coronavirus as President Trump fumes". The Washington Post. from the original on 15 June 2021. Retrieved 19 July 2021.
214. Singh M, Davidson H, Borger J (1 May 2020). "Trump claims to have evidence coronavirus started in Chinese lab but offers no details". The Guardian. from the original on 18 July 2021. Retrieved 18 July 2021.
215. Lima C (26 May 2021). "Facebook no longer treating 'man-made' Covid as a crackpot idea". Politico. from the original on 26 July 2021. Retrieved 27 July 2021.
216. Hern A (27 May 2021). "Facebook lifts ban on posts claiming Covid-19 was man-made". The Guardian. from the original on 5 July 2021. Retrieved 27 July 2021.
217. Kirchgaessner S, Graham-Harrison E, Lily K (11 April 2020). "China clamping down on coronavirus research, deleted pages suggest". The Guardian. from the original on 11 April 2020. Retrieved 29 July 2021.
218. Areddy JT (26 May 2020). "China Rules Out Animal Market and Lab as Coronavirus Origin". Wall Street Journal. from the original on 17 February 2021. Retrieved 29 May 2020.
219. Alba D (19 March 2021). "How Anti-Asian Activity Online Set the Stage for Real-world Violence". The New York Times. from the original on 16 June 2021. Retrieved 20 July 2021.
220. Bloom JD, Chan YA, Baric RS, Bjorkman PJ, Cobey S, Deverman BE, Fisman DN, Gupta R, Iwasaki A, Lipsitch M, Medzhitov R, Neher RA, Nielsen R, Patterson N, Stearns T, van Nimwegen E, Worobey M, Relman DA (14 May 2021). "Investigate the origins of COVID-19". Science. 372 (6543): 694. Bibcode:2021Sci...372..694B. doi:10.1126/science.abj0016. PMC 9520851. PMID 33986172. S2CID 234487267. from the original on 17 June 2021. Retrieved 14 January 2022.
221. Gan N, Yeung J (28 May 2021). "China counters Biden's Covid probe with a US military base conspiracy theory". CNN. from the original on 28 June 2022. Retrieved 28 June 2022.
222. Buckley C (22 July 2021). "China denounces the W.H.O.'s call for another look at the Wuhan lab as 'shocking' and 'arrogant.'". The New York Times. ISSN 0362-4331. from the original on 24 July 2021. Retrieved 24 July 2021.
223. Schafer B (9 July 2021). "China Fires Back at Biden with Conspiracy Theories About Maryland Lab". Foreign Policy. from the original on 27 July 2021. Retrieved 26 July 2021.
224. Thacker PD (1 October 2021). "Covid-19: Lancet investigation into origin of pandemic shuts down over bias risk". BMJ. 375: n2414. doi:10.1136/bmj.n2414. PMID 34598923. S2CID 238241044.
225. Lonas L (9 June 2021). "WHO adviser accuses COVID-19 lab-leak theory critics of 'thuggery'". The Hill. from the original on 24 June 2021.
226. "Did COVID-19 Leak From A Lab? A Reporter Investigates — And Finds Roadblocks". National Public Radio. from the original on 18 June 2021. Retrieved 19 June 2021.
227. Hibbett M, Grim R (12 January 2022). "House Republicans Release Text of Redacted Fauci Emails on Covid Origins". The Intercept. from the original on 15 January 2022. Retrieved 16 January 2022.
228. Dilanian K, Perrette A, Chow D (4 June 2021). "Fauci's emails don't prove a Wuhan conspiracy, but raise further questions". NBC News.

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